The most informative method for diagnosing pneumonia is. Methods for diagnosing pneumonia. Laboratory diagnosis of community-acquired pneumonia

1. In the blood test for acute pneumonia, there is
1. leukocytosis,
2. accelerated ESR
3. agranulocytosis
4. leukopenia
5. erythrocytosis

2. The criterion for stopping antibiotic therapy in acute pneumonia is:

a) temperature normalization

b) a period of 3-4 days after the temperature normalizes

c) a period of 8-10 days after the temperature normalizes

d) resorption of pneumonic infiltration

e) normalization of peripheral blood parameters

3. Crepitus is heard when:

a) bronchitis

b) bronchial asthma

c) croupous pneumonia

d) dry pleurisy

e) exudative pleurisy

4. The main causative agent of croupous pneumonia

a) gonococcus

b) pneumococcus

c) streptococcus

d) staphylococcus aureus

e) Koch's wand

5. The most informative method for diagnosing pneumonia

a) sputum analysis

b) blood test

c) chest x-ray

d) pleural puncture

e) fluorography

6. Complication of focal pneumonia

a) lung abscess

b) bronchitis

c) tuberculosis

d) lung cancer

e) toxic damage to points

7. Complication of croupous pneumonia

a) bronchial asthma

b) bronchitis

c) pleurisy

d) lung cancer

e) gangrene of the lung

8. A 32-year-old patient was admitted with complaints of cough with rusty sputum, pain in the right side, aggravated by coughing, chills, fever up to 39 0 , shortness of breath. Acutely ill after cooling. On admission, the patient was in a serious condition. With percussion below the angle of the scapula - dullness of percussion sound, weakened breathing, crepitus in the same place. What is the condition of the patient?

a) lobar pneumonia

b) bronchopneumonia

d) tuberculosis

e) acute bronchitis

9. A 25-year-old patient, upon admission to the hospital, complains of cough, sharp pain in the abdominal cavity on the right, nausea, and vomiting. Objectively: temperature is 39.7 0 C, feverish blush on the cheeks. The chest on the right lags behind in breathing. During percussion - shortening of the percussion sound on the right, below the angle of the scapula, breathing is weakened there, crepitus is heard. With deep palpation of the epigastric region, the pain does not increase, there is no tension in the muscles of the anterior abdominal wall and there are no symptoms of peritoneal irritation. Complete blood count: leukocytosis, increased ESR. What is the condition of the patient?

a) lower lobe pneumonia

b) acute abdomen

d) tuberculosis

e) acute bronchitis

10. A 24-year-old patient was delivered with complaints of high fever, pain in the right side associated with breathing, dry cough, and headache. I got acutely ill. In the evening, when I came home from work, I felt healthy. After dinner, she felt chills, weakness. There were pains in the right side, he cannot breathe deeply because of the pains. Objectively: the patient's condition is grave. He holds his right side with his hand, groans from pain. The face is hyperemic, a blush on the right cheek. There is herpes on the lips. On percussion, dullness of the lung sound to the right of the angle of the scapula, weakened breathing in the same place, crepitus is heard. In the general analysis of blood leukocytosis.

What is the patient's condition?

a) lobar pneumonia

c) acute bronchitis

d) pulmonary tuberculosis

e) focal pneumonia

11. Croupous pneumonia is

a) inflammation of one segment of the lung

b) inflammation of the lobe of the lung

c) inflammation of the bronchi

d) proliferation of connective tissue

e) inflammation of the lymph nodes of the mediastinum

12. Acute onset, high fever, chest pain when coughing, herpes on the lips are characteristic of

a) croupous pneumonia

b) focal pneumonia

c) pneumosclerosis

d) bronchial asthma

e) tuberculosis

13. "Rusty character" of sputum is observed when

a) bronchial asthma

b) acute bronchitis

c) focal pneumonia

d) lobar pneumonia

e) dry pleurisy

14. In case of pneumonia, all of the listed drugs are prescribed, except:

a) antibiotics

b) expectorants

c) bronchospasmolytic

d) antipyretic

e) narcotic

15. Croupous pneumonia is

1. inflammation of the lobe of the lung

2. inflammation of the lung lobule

3. formation of a purulent cavity in the lung tissue

4. lung necrosis

5. pneumothorax

Characteristic signs of croupous pneumonia

A. intoxication, cough, chest pain, cachexia

B. cough, shortness of breath, pulmonary hemorrhage

C. hemoptysis, cough, chest pain, shortness of breath

D. shortness of breath, discharge of purulent sputum in the morning

Answers:

16. Etiopathogenesis of respiratory failure in pneumonia:

a) violation of the diffusion of gases

b) pulmonary hypertension

c) hypertrophy of the right half of the heart

d) decrease in myocardial contractility

e) exsicosis

17. The main causative agent of pneumonia

b) mycobacterium

c) pneumococcus

d) Escherichia coli

e) Escherichia

18. Inflammation of an entire lobe of the lung is observed when

a) acute bronchitis

b) bronchial asthma

c) pneumonia

d) dry pleurisy

e) exudative pleurisy

19. The most informative method for diagnosing pneumonia

a) blood test

b) sputum analysis

c) pleural puncture

d) chest X-ray

e) fluorography

20. Etiotropic treatment of pneumonia is the use

a) bronchodilators

b) expectorants

c) antibiotics

d) antipyretic

e) antispasmodics

21. Complication of pneumonia -

a) pulmonary hemorrhage

b) fever

c) chest pain

d) acute respiratory failure

e) acute heart failure

22. The main symptoms of pneumonia:

a) weakness, headache, glassy sputum

b) chest pain, shortness of breath, fever

c) prolonged subfebrile condition, fatigue

d) edema, increased blood pressure, rhythm disturbance

e) rhythm disturbance, prolonged subfebrile condition

23. The most common cause of chronic cor pulmonale is

a) lung cancer

b) chest deformity

c) primary pulmonary hypertension

d) obstructive pulmonary disease

e) recurrent embolism of the branches of the pulmonary artery

24.Pneumonia is

1.inflammation of the parenchyma of the lung

2. inflammation of the pleural sheets

3.inflammation of the bronchial mucosa

4. accumulation of air in the pleural cavity

5. accumulation of fluid in the pleural cavity

Etiopathogenesis of respiratory failure in pneumonia

A. violation of the diffusion of gases

B. pulmonary hypertension

C. hypertrophy of the right half of the heart

D. decrease in myocardial contractility

D.exicosis

Answers:

25. After acute pneumonia, dispensary observation is carried out for

Diagnosis of pneumonia is necessary for the timely detection of pneumonia and the treatment of this formidable disease. Also, diagnostics helps to verify the accuracy of the diagnosis made by the doctor, identify the causes of the disease, and determine the severity of inflammation.

The concept of diagnostics

Diagnosis of pneumonia includes differential (delimiting) diagnosis with other pathology of the lungs, visual examination of the patient, listening (auscultation), tapping (percussion), radiography, laboratory and radiation diagnosis, computed tomography, spirography.

The doctor first collects an anamnesis (the history of the onset of the disease and its course), where he records data on recent colds, concomitant chronic diseases, examines the skin, chest and intercostal spaces, assesses the general condition of the patient and prescribes a number of tests.

A good specialist can diagnose pneumonia based on the data of examination and listening to the respiratory organs, but he uses confirmatory methods to prescribe a clear treatment regimen for the disease.

Listening to the lungs

Auscultation for pneumonia is based on listening to the respiratory organs with phonendoscopes and stethoscopes.

It is possible to understand that a patient has pneumonia during auscultation by the following signs:

1. Fine bubbling moist rales are heard.
2. Bronchial breathing (bronchophony) and weakening and shortening of the lung sound are clearly audible.
3. Inspiratory crepitus of pneumonia is audible - its clear sign (a specific sound at the moment of exhalation).

The absence of wheezing in the lungs indicates that there is no pneumonia.

Listening to the lungs should be carried out correctly:

1. The chest and back of the patient are exposed so that the linen does not interfere with the differentiation of sounds with unnecessary noise.
2. If men have a lot of hair, then they are not moistened with cold water or a greasy cream so that the friction of the stethoscope on the hair does not interfere with the ear.
3. Listening should be in silence and at room temperature, as muscle contraction due to the surrounding coolness can simulate other sounds.
4. The tube should fit snugly and painlessly against the patient's skin with finger fixation so as not to generate unnecessary noise.
5. Auscultation must necessarily compare symmetrical parts of the respiratory organs.
6. Listening begins at the top of the lung and down the lateral and posterior sections.

Percussion (tapping) is a physical method based on a special tapping of the borders of the lung with finger blows, with the doctor evaluating the resulting sounds.

This method allows you to determine the pathology of the lungs and pleural cavity by comparing percussion sound in the same areas and determine the size and shape of the organ. The method is based on knowledge of the nature of the emerging sounds that exist normally.

Example: a dull tympanic sound is heard at the beginning and end of lobar pneumonia.

Correct percussion consists in applying two deaf blows with fingers in short time intervals on the chest in order to establish the location of the field of the lungs and their airiness. With pneumonia, they are dense (especially with croupous inflammation of the lungs).

Percussion for pneumonia is considered the best method of diagnosing in children of all ages.

x-ray

This is the main and most informative method for diagnosing pneumonia, based on the use of special rays. X-ray allows you to monitor the respiratory organs during therapy with an assessment of its effectiveness.

The radiograph is performed in three projections: direct, lateral (right or left) and in one of the oblique. The photo must be clear. Changes in x-ray images during inflammation occur by the third day of illness. An early x-ray shows an enhanced lung pattern, which happens with other diseases.

X-ray reveals enlarged lymph nodes of the mediastinum, characterizes the shadows that have appeared, shows how the root of the bronchus was deformed during inflammation, detects basal infiltration, the focus of inflammation itself. X-rays are repeated one month after therapy with an assessment of its effectiveness.

X-ray diagnosis of pneumonia shows the following:

• focal, lobar or segmental blackouts;
• deformation of the lung tissue pattern;
• strengthening of the root of the lung and lymphadenitis;
• processes of inflammation in the pleura;
• visible exudate.

In the pictures, the foci of inflammation are represented by darkening of tissues of different density and prevalence. There is a blackout of the focus, poly-segmental blackout, subtotal and total.

The limited infiltrate does not go beyond the segmental department. A subtotal focus is found when one or two lobes of the lung are inflamed. Such signs are characteristic of croupous inflammation and complications.

If in 7 days the infiltrate on the X-ray film does not disappear, then this indicates viral pneumonia.

The pattern appears due to increased blood supply and reduced lung capacity. The radiograph looks like a lattice, but only in the place of the focus. When airiness rises, the fields of the lung in the picture are transparent.

The radiograph for inflammation of the lungs during recovery is characterized by the fact that:

• the intensity of dimming decreases;
• the size of the shadow decreases;
• the root of the lung expands;
• the pulmonary pattern is enriched (many small elements appear on the entire surface of the lung).

An expanded root can be then for several months in a row, until the lung tissue is completely restored.

Laboratory diagnostics

Laboratory diagnosis of pneumonia consists in various studies of blood, sputum, bronchial lavage, pleural fluid, urine, the use of immunological tests on the skin to detect allergens to antibacterial drugs, etc.

Methods for laboratory diagnosis of pneumonia:

1. Clinical blood tests show signs of pneumonia in the form of moderate or increased leukocytosis, accelerated ESR, a shift in the increase in the neutrophil formula to the left, with pathological granularity.
2. Blood biochemistry is a study of C-reactive protein in pneumonia (in violation of protein metabolism), glycemic level, globulin growth, low serum activity, liver enzymes (ALT, AST), etc. It is prescribed when determining pathological processes, concomitant diseases that make treatment difficult pneumonia.
3. The microbiology of blood samples is used in the cultivation of microbes on nutrient media in patients who require hospitalization in the intensive care unit.
4. Blood serology is used in the diagnosis of viruses such as mycoplasmas, chlamydia, legionella. Assign when there is suspicion of SARS.
5. The immunological indicator characterizes a moderate decrease in T - lymphocytes and an increase in their activity (Ig G) and a decrease (Ig A) (with mycoplasmal pneumonia).
6. Blood clotting is determined by tests that reflect the process in the lung tissue to prevent bleeding, thrombosis and arterial embolism.
7. Sputum and bronchial lavage are examined: bacterioscopy of Gram-stained smears, laboratory examination of cultures, sensitivity to antibacterial drugs is determined. Microbiology is done when the effect of antibiotic treatment does not occur within the first seven days after diagnosis.
8. Sputum studies allow you to find out the nature of the pathological process. The number and color indicate purulent processes in the lungs and the presence of complications. With pneumonia, sputum is mucous, purulent, with an admixture of blood - rusty. The consistency is viscous or sticky (with croupous inflammation), liquid (with the onset of pulmonary edema). Smell - with pneumonia, it is odorless. If the smell is present, there are complications in the form of abscesses, gangrene. Look at the composition and clots. There are always white blood cells in sputum.
9. Examine sputum for the presence of fungus and other microorganisms - conduct sputum cultures and identify them, as well as identify their sensitivity to antibiotics
10. Pleural puncture is used when it is necessary to remove fluid or air from the pleural cavity, as well as to introduce therapeutic agents into the pleura for pleurisy that has arisen as a complication of pneumonia. The pleural fluid is examined cytologically, evaluated physically, chemically, microscopically in native and stained preparations.
11. Determination of arterial blood gases is used in patients with signs of respiratory failure.
12. A general urinalysis and an additional express method are prescribed when legionella is detected, due to which patients often die.
13. Blood bacteriology is done in the presence of a pathological process. It helps to correct treatment in a hospital setting.

Radiation diagnostics

Radiation diagnosis of pneumonia is of great importance in the correct diagnosis and determination of the focus of inflammation and consists of a number of methods that use the action of rays.

Methods of radiation diagnosis of pneumonia include:

1. Plain x-ray examination of the respiratory organs with two projections. Modern technologies for exposure to X-rays are significant and harmless.
2. Computed tomography (CT) of the lungs. This method allows you to view in detail images of foci that are in depth and determine changes.
3. Ultrasound examination (ultrasound) allows you to make an assessment of the condition of the pleura and its cavity with exudate and inflammation. Ultrasound is prescribed to clarify the entire characteristics of pulmonary processes.

Radiation diagnostics is needed to establish the size of pulmonary changes and the sequence of the developing inflammatory process in the lobes of the lung.

Pregnant women are not prescribed radiation diagnostics!

CT scan of the lungs

A tomogram of the lung tissue is prescribed when the patient is suspected to have inflammation at the root in order to carefully examine the lung tissue with pneumonia. CT reveals changes not only in the parenchyma at different angles, but also in the mediastinum. The computer converts the contrast study into a cross-sectional image, which is reconstructed on the monitor screen, slide film in several modes.

CT for pneumonia allows you to get a layered image with the level of the roots of the lung. Here, a beam of pulsed x-ray radiation passes through a layer of lung tissue.

Lung tomography is performed at a low intensity of the x-ray image of the lungs, when it is necessary to distinguish between several types of pathology of the respiratory organs, with detailed focusing of a given layer that is motionless in relation to the x-ray film during the entire time of the procedure.

CT helps to recognize focal changes and decay of lung tissue and has the following advantages: higher sensitivity (than X-ray), safety, painlessness, efficiency and high accuracy (up to 94%), makes it possible to prevent complications. But the early stages of pneumonia reduce its accuracy. CT devices can significantly reduce the radiation dose of the procedure.

Spirography is a recording of registration changes in lung volumes by a graphical method during movements during breathing to obtain an indicator that describes pulmonary ventilation using special devices - spirographs.

This method describes the airiness of volumes and capacity (a characteristic of elasticity and stretching of the respiratory organs), as well as the dynamics of the indicator for determining the amount of air passing through the lung tissue during inhalation and exhalation for the accepted time unit. Indicators are determined by the mode of calm breathing and forced breathing maneuvers to detect bronchial-pulmonary obstruction.

Spirography for pneumonia is indicated in such cases:

1. When it is necessary to determine the type and degree of pulmonary insufficiency, and at the initial signs.
2. When you need a monitoring analysis of all indicators of the ventilation capacity of the respiratory system and the determination of the degree of rapidity of the disease.
3. In order to conduct a delimiting diagnosis of lung and heart failure.

The spirography data are plotted as a curve: first with quiet breathing - then with deep breathing - then maneuvers with the deepest inhalation, and then with a fast and long (6 s) exhalation, with the determination of forced vital capacity (FVC). Then, the maximum ventilation of the lungs is recorded for 1 min. There are generally accepted norms for the volume of FVC. They determine deviations and measure the patency of the trachea and bronchi in pneumonia.

To recognize pneumonia using all diagnostic methods, you need to consult a doctor in time, as medicine has many means of diagnosing pneumonia in order to prevent the occurrence of formidable complications.

Diagnosis of pneumonia is based on the identification of the 5 most simple and fairly informative clinical, laboratory and instrumental signs, called the "gold standard" of diagnosis:

1. Acute onset of the disease, accompanied by an increase in body temperature above 38 C.
2. Sudden onset or marked increase in cough with sputum, predominantly purulent and/or hemorrhagic.
3. The appearance of previously absent local dullness (shortening) of percussion sound and the auscultatory phenomena described above, which are characteristic of lobar (croupous) or focal pneumonia (weakening of breathing, bronchial breathing, crepitus, moist fine bubbling sonorous rales, pleural friction noise).
4. Leukocytosis or (more rarely) leukopenia in combination with a neutrophilic shift.
5. X-ray signs of pneumonia - focal inflammatory infiltrates in the lungs, which were not previously detected.

Nevertheless, modern approaches to the etiotropic treatment of patients with pneumonia require a number of additional laboratory and instrumental tests for the possible identification of the pathogen, differential diagnosis of lung damage, assessment of the functional state of the respiratory system, and timely diagnosis of complications of the disease. To this end, in addition to chest X-ray, general and biochemical blood tests, the following additional studies are envisaged:

• sputum examination (microscopy of a stained preparation and culture to identify the pathogen);
• assessment of the function of external respiration;
• study of blood gases and oxygen saturation of arterial blood (in cases
• severe pneumonia to be treated in the ICU;
• repeated blood tests “for sterility” (if bacteremia and sepsis are suspected);
• x-ray computed tomography (with insufficient information content of traditional x-ray examination);
• pleural puncture (in the presence of effusion) and some others.

The choice of each of these methods is individual and should be based on an analysis of the characteristics of the clinical picture of the disease and the effectiveness of the diagnosis, differential diagnosis and treatment.

Radiological diagnosis of pneumonia

X-ray methods of research are of decisive importance in the diagnosis of pneumonia. Currently, the clinic widely uses such methods as fluoroscopy and radiography of the chest, tomography, computed tomography. The practitioner should have a good understanding of the possibilities of these methods in order to correctly select the most informative of them in each specific case of the disease and, if possible, reduce the radiation exposure to the patient.

Fluoroscopy

It should be borne in mind that one of the most accessible and common methods of X-ray examination - chest X-ray - has a number of significant drawbacks, namely:

1. is distinguished by the well-known subjectivity of the interpretation of the x-ray picture,
2. does not make it possible to objectively compare radiological data obtained during repeated studies and
3. accompanied by a large radiation load on the patient and medical staff.

Therefore, the scope of the method of fluoroscopy in clinical practice, apparently, should be limited to the study of the organs of the chest in the process of their movement (for example, the study of the mobility of the diaphragm, the nature of the movements of the heart during its contraction, etc.) and the refinement of the topography of pathological changes in the lungs when using different positions of the patient.

Radiography

The main method of X-ray examination of the respiratory organs is radiography in two projections - direct and lateral, which allows obtaining objective and documented information about the state of the chest organs. In this case, it is necessary, if possible, to outline not only the nature of the pathological process, but also to accurately determine its localization, corresponding to the projection of one or another lobe of the lung and pulmonary segments.

The radiological diagnosis of pneumonia is based on the results of a lung field examination, including an assessment of:

• features of the lung pattern;
• conditions of the roots of the lungs;
• the presence of widespread or limited darkening of the lung fields (compaction of the lung tissue);
• the presence of limited or diffuse enlightenment of the lung tissue (increased airiness).

Of great importance is also the assessment of the condition of the skeleton of the chest and the determination of the position of the diaphragm.

The roots of the lungs, located in the middle zone of the lung fields between the anterior ends of the II and IV ribs, are formed by the shadows of the branches of the pulmonary artery and pulmonary veins, as well as large bronchi. Depending on their location in relation to the plane of the screen, they are presented on an x-ray in the form of branching strips or clear rounded or oval formations. The shadows of the vessels that form the root of the lung continue beyond it in the lung fields, forming a pulmonary pattern. Normally, it is clearly visible in the central basal zone, and on the periphery it is represented by only a few, very small vascular branches.

Below is a brief description of the x-ray pattern characteristic of two clinical and morphological variants of pneumonia (croupous and focal), as well as some features of x-ray changes in pneumonia of various etiologies.

Tomography

Tomography is an additional method of “layered” X-ray examination of organs, which is used in patients with pneumonia for a more detailed study of the pulmonary pattern, the nature of the pathological process in the lung parenchyma and interstitium, the state of the tracheobronchial tree, the roots of the lungs, mediastinum, etc.

The principle of the method is that as a result of the synchronous movement of the X-ray tube and the film cassette in the opposite direction, a sufficiently clear image of only those parts of the organ (its “layers”) that are located at the center level, or the axis of rotation of the tube and cassette, is obtained on the film. All other details ("elephant"), which are outside this plane, seem to be "smeared", their image becomes blurred.

To obtain a multilayer image, special cassettes are used, in which several films are placed at the required distance from each other. More often, the so-called longitudinal tomography is used, when the allocated layers are in the longitudinal direction. The "swing angle" of the tube (and cassette) is usually 30-45°. This method is used to study the pulmonary vessels. To evaluate the aorta, pulmonary artery, inferior and superior vena cava, it is better to use transverse tomography.

In all cases, the choice of the depth of the tomographic study, the exposure value, the swing angle and other technical parameters of the study is carried out only after analyzing the previously made x-ray image.

In diseases of the respiratory organs, the tomography method is used to clarify the nature and individual details of the pathological process in the lungs, as well as to assess morphological changes in the trachea, bronchi, lymph nodes, blood vessels, etc. This method is especially important in the study of patients in whom there is a suspicion of the presence of a tumor process in the lungs, bronchi and pleura.

Screening program for suspected pneumonia

According to the consensus of the Russian Congress of Pulmonologists (1995), the following amount of research is recommended for pneumonia.

1. Studies required for all patients
   • clinical examination of patients;
   • clinical blood test;
   • radiography of the lungs in two projections;
   • bacterioscopy of sputum stained by Gram;
   • sputum culture with a quantitative assessment of the flora and the determination of its sensitivity to antibiotics;
   • general urine analysis.
2. Research conducted according to indications
   • study of the function of external respiration in violation of ventilation;
   • study of blood gases and acid-base balance in severe patients with respiratory failure;
   • pleural puncture followed by examination of the pleural fluid in patients with fluid in the pleural cavity;
   • tomography of the lungs in case of suspected destruction of lung tissue or neoplasm of the lung;
   • serological tests (detection of antibodies to the pathogen) - for atypical pneumonia;
   • biochemical blood test for severe pneumonia in people over 60 years of age;
   • fibrobronchoscopy - if a tumor is suspected, with hemoptysis, with a prolonged course of pneumonia;
   • study of the immunological status - with a protracted course of pneumonia and in persons with signs of immunodeficiency;
   • lung scintigraphy - if PE is suspected.

X-ray signs of croupous pneumonia

high tide

The earliest x-ray change that occurs on the first day of lobar pneumonia (tide stage) is an increase in the pulmonary pattern in the affected lobe, due to an increase in the blood supply to the vessels of the lungs, as well as inflammatory edema of the lung tissue. Thus, in the stage of the tide, there is an increase in both the vascular and interstitial components of the pulmonary pattern.

There is also a slight expansion of the lung root on the side of the lesion, its structure becomes not so distinct. At the same time, the transparency of the lung field practically does not change or slightly decreases.

If the focus of developing croupous pneumonia is located in the lower lobe, there is a decrease in the mobility of the corresponding dome of the diaphragm.

Hepatization stage

The stage of hepatization is characterized by the appearance on the 2-3rd day from the onset of the disease of intense homogeneous darkening, corresponding to the projection of the affected lobe of the lung. The intensity of the shadow is more pronounced on the periphery. The size of the affected lobe is slightly enlarged or not changed; a decrease in the volume of the share is observed relatively rarely. Expansion of the lung root on the side of the lesion is noted, the root becomes non-structural. The pleura is sealed. The lumen of the large bronchi with croupous inflammation of the lungs remains free.

Resolution stage

The resolution stage is characterized by a gradual decrease in the intensity of the shadow and its fragmentation. With an uncomplicated course of pneumonia, complete resorption of the infiltrate occurs in 2.5-3 weeks. In other cases, at the site of the affected lobe, there is an increase in the pulmonary pattern with areas of its deformation, which is an x-ray sign of pneumofibrosis. At the same time, a slight compaction of the pleura is preserved.

X-ray signs of focal pneumonia

Focal bronchopneumonia is characterized by infiltration of the alveolar and interstitial tissue and involvement in the inflammatory process of the lung root on the side of the lesion. At the initial stages of the disease, there is a local increase in the pulmonary pattern and a slight expansion of the lung root. After some time, relatively small (from 0.3 to 1.5 cm in diameter) and various foci of infiltration (darkening) begin to be detected in the lung field. They are characterized by multiplicity, different sizes, low shadow intensity, blurred outlines and, as a rule, are accompanied by an increase in the pulmonary pattern. The roots of the lungs become enlarged, poorly structured, with fuzzy contours.

Often, slightly enlarged peribronchial lymph nodes are found. There is also limited mobility of the dome of the diaphragm.

In uncomplicated cases, under the influence of anti-inflammatory treatment, a positive dynamics of the x-ray picture is usually observed, and after 1.5-2 weeks, the pulmonary infiltrates resolve. Sometimes bronchopneumonia can be complicated by reactive pleurisy or destruction of lung tissue.

X-ray signs of staphylococcal pneumonia

The X-ray picture of staphylococcal pneumonia is characterized by the presence of multiple inflammatory infiltrates, often located in both lungs. Inflammatory infiltrates often merge. There is a tendency for them to disintegrate with the formation of limited enlightenment against the background of shadows with a horizontal liquid level. With the "bullous form" of pneumonia, the cavities can disappear without a trace in some places and appear in others. Often there is an effusion in the pleural cavity.

After the resolution of staphylococcal pneumonia, the strengthening of the pulmonary pattern persists for a long time, and in some cases areas of pneumosclerosis are formed, cysts remain in place of the cavities, and compaction of the pleural sheets (moorings) is preserved.

X-ray signs of pneumonia caused by Klebsiella

A feature of Friedlander's pneumonia caused by Klebsiella is the extensiveness of the lesion of the lung tissue, which radiologically manifests itself from the first days of the disease. Multiple large or smaller inflammatory infiltrates quickly merge with each other, capturing large areas of the lung, often corresponding to the projection of an entire lobe of the lung (“pseudo-lobar” pneumonia). Quite quickly, multiple disintegration cavities appear in the infiltrate, which also tend to merge and form large cavities with a horizontal liquid level. Often the disease is complicated by the development of exudative pleurisy.

The course of Friedlander's pneumonia is long (up to 2-3 months). After recovery, as a rule, areas of pronounced pneumosclerosis and lung carnification remain. Often bronchiectasis is formed, and the pleural cavity is partially obliterated.

X-ray signs of pneumonia caused by intracellular pathogens

In legionella pneumonia, radiological changes are diverse. Most often, multiple infiltrates are detected in both lungs, which later merge into an extensive lobar opacification. Tissue breakdown and abscess formation are rare. Resorption of infiltrates and normalization of the X-ray picture in an uncomplicated course of the disease occurs after 8-10 weeks.

With mycoplasmal pneumonia, only local amplification and deformation of the lung pattern, reflecting infiltrations of the interstitial tissue, can be determined on radiographs. In some patients, low-intensity focal shadows appear on this foyer, tending to merge. Normalization of the x-ray picture occurs after 2-4 weeks.

With chlamydial pneumonia, focal strengthening and deformation of the lung pattern, expansion of the lung root and the reaction of the pleura in the form of its compaction are also initially determined. In the future, against this background, numerous inflammatory foci, of low intensity, with fuzzy contours, may appear. After their disappearance on the background of treatment, an increase in the pulmonary pattern persists for a long time, sometimes disk-shaped atelectasis is visible. Normalization of the x-ray picture occurs in 3-5 weeks.

Computed tomography for pneumonia

Computed tomography (CT) is a highly informative method of X-ray examination of a patient, which is becoming increasingly common in clinical practice. The method is distinguished by its high resolution, which makes it possible to visualize lesions up to 1–2 mm in size, the possibility of obtaining quantitative information on tissue density, and the convenience of presenting an x-ray picture in the form of thin (up to 1 mm) sequential transverse or longitudinal “sections” of the organs under study.

The translucence of each tissue layer is carried out in a pulsed mode using an X-ray tube with a slit collimator, which rotates around the longitudinal axis of the patient's body. The number of such transmissions at different angles reaches 360 or 720. Each time X-rays pass through a layer of tissue, the radiation is attenuated, depending on the density of the individual structures of the layer under study. The degree of X-ray attenuation is measured by a large number of special highly sensitive detectors, after which all the information received is processed by a high-speed computer. As a result, an image of a section of an organ is obtained, in which the brightness of each coordinate point corresponds to the density of the tissue. Image analysis is carried out both in automatic mode using a computer and special programs, and visually.

Depending on the specific tasks of the study and the nature of the pathological process in the lungs, the operator can choose the thickness of the axial sections and the direction of tomography, as well as one of three study modes.

1. Continuous CT, when all sections of the organ are sequentially imaged without exception. This method of tomography makes it possible to obtain maximum information about morphological changes, but is characterized by a large radiation exposure and cost of research.
2. Discrete CT with a given relatively large interval between slices, which significantly reduces the radiation exposure, but leads to the loss of part of the information.
3. Targeted CT consists in a thorough layer-by-layer examination of one or more areas of the organ of interest to the doctor, usually in the area of ​​a previously identified pathological formation.

Continuous CT of the lungs allows you to get maximum information about the pathological changes in the organ and is indicated primarily for volumetric processes in the lungs, when the presence of lung cancer or metastatic organ damage is not excluded. In these cases, CT makes it possible to study in detail the structure and size of the tumor itself and to clarify the presence of metastatic lesions of the pleura, lymph nodes of the mediastinum, roots of the lungs and retroperitoneal space (with CT scan of the abdominal cavity and retroperitoneal space).

Discrete CT is more indicated for diffuse pathological processes in the lungs (pyeumoconiosis, alveolitis, chronic bronchitis, etc.), when surgical treatment is expected.

Targeted CT is used mainly in patients with an established diagnosis and an established nature of the pathological process, for example, to clarify the contour of a volumetric formation, the presence of necrosis in it, the state of the surrounding lung tissue, etc.

Computed tomography has significant advantages over conventional X-ray examination, since it allows to detect finer details of the pathological process. Therefore, the indications for using the CT method in clinical practice are, in principle, quite wide. The only significant factor limiting the application of the method is its high cost and its low availability for some medical institutions. Taking this into account, one can agree with the opinion of a number of researchers that "the most common indications for CT of the lungs arise in cases where the information content of a conventional X-ray examination is insufficient for making a heavy diagnosis and the results of CT can affect the treatment tactics."

In patients with pneumonia, the need for CT is about 10%. With CT, infiltrative changes in the lungs are detected at earlier stages of the development of the disease.

General clinical blood test for pneumonia

A general clinical blood test is included in the mandatory examination plan for all inpatients and outpatients with pneumonia. The greatest diagnostic value is counting the number of leukocytes, determining the leukocyte formula and ESR.

White blood cell count

Normally, the total number of leukocytes is (4.0-8.8) x 109 / l.

Leukocytosis is characteristic of most patients with bacterial pneumonia. It indicates an acceleration of the maturation of leukocytes in the hematopoietic organs under the influence of numerous natural stimulants of leukopoiesis: physical and chemical factors of inflammation, including inflammatory mediators, tissue breakdown products, hypoxemia, formed immune complexes, some toxic substances, increased functions of the pituitary-adrenal system, which controls the process of maturation of leukocytes, and others. Most of these factors are natural signals to activate the protective functions of leukocytes.

Leukocytosis in patients with pneumonia in most cases reflects a satisfactory reactivity of the bone marrow hematopoiesis system in response to the action of external and internal stimulants of leukopoiesis. At the same time, leukocytosis is a fairly sensitive marker of the severity of the inflammatory process in the lungs.

At the same time, it should be remembered that with pneumonia caused by chlamydia, in most cases, moderate leukopenia is observed (a decrease in the number of leukocytes is less than 4.0 x 10 ° / l). With mycoplasmal pneumonia, the total number of leukocytes usually remains normal (about 8.0 x 109 / l), although leukocytosis or leukopenia is determined in 10-15% of cases. Finally, viral infections are usually accompanied by an increase in ESR and a normal or low white blood cell count (leukopenia).

In all other cases of bacterial pneumonia caused by pneumococci, streptococci, staphylococci, Haemophilus influenzae, legionella, Klebsiella, Pseudomonas aeruginosa, etc., the appearance of leukopenia, as a rule, indicates a significant inhibition of leukopoiesis in the hematopoietic organs and is a very unfavorable prognostic sign. This is more often observed in the elderly, malnourished and debilitated patients, which is associated with a decrease in immunity and overall body resistance. In addition, it should be remembered that leukopenia may be associated with the use of certain drugs (antibiotics, cytostatics, non-steroidal anti-inflammatory drugs, etc.) and autoimmune processes that complicate, in particular, the course of pneumonia.

Leukocytosis is characteristic of most patients with bacterial pneumonia. The exceptions are pneumonia caused by chlamydia and mycoplasma, as well as most viral infections, in which moderate leukopenia or a normal white blood cell count can be observed.

The appearance of leukopenia in patients with bacterial pneumonia may indicate a significant inhibition of leukopoiesis and is a very unfavorable prognostic sign, indicating a decrease in immunity and overall body resistance. In addition, leukopenia can develop during treatment with antibiotics, cytostatics and non-steroidal anti-inflammatory drugs.

Leukocyte formula

The leukocyte formula is the percentage of different types of leukocytes in peripheral blood. The calculation of the leukocyte formula is carried out by immersion microscopy of stained smears stained according to Romanovsky-Giemsa or other methods.

Differentiation of various types of leukocytes and calculation of the leukocyte formula requires a good knowledge of the morphological features of various leukocytes and the general pattern of hematopoiesis. The myeloid series of hematopoiesis is represented by cells of granulocytic, megakaryocytic, monocytic and erythrocyte hematopoietic lineages.

Granulocytes are blood cells, the most characteristic morphological feature of which is a pronounced granularity of the cytoplasm (neutrophilic, eosinophilic or basophilic). These cells have a common precursor and a single evolution up to the promyelocyte stage, after which there is a gradual differentiation of granulocytes into neutrophils, eosinophils and basophils, which differ significantly from each other in their structure and function.

Neutrophils have abundant, fine, dusty granules of pinkish-violet color. Mature eosinophils are distinguished by large, occupying the entire cytoplasm, granularity, which has a scarlet color (“ketova caviar”). The granularity of basophils is large, heterogeneous, dark purple or black.

Young immature cells of granulocytes (myeloblast, promyelocyte, neutrophilic, eosinophilic and basophilic myelocytes and megamyelocytes) are larger in size, have a large round or slightly concave nucleus with a more delicate and fine pattern and light color. Their nuclei often contain nucleoli (nucleoli).

Mature granulocytes (stab and segmented) are smaller, their nuclei are darker in color, they look like curved rods or separate segments connected by a “thread” of the nuclear substance. The nuclei do not contain nucleolus.

The cells of a monocytic germ are characterized by a pale blue or grayish color of the cytoplasm, devoid of the pronounced granularity that is characteristic of granulocytes. In the cytoplasm, only individual small azurophilic granules, as well as vacuoles, can be found. In immature cells of the monocytic series (monoblast, promonocyte), the nucleus is large and occupies most of the cell. The nucleus of a mature monocyte is smaller and looks like a butterfly or mushroom, although it can often take quite bizarre shapes.

The cells of the lymphoid germ of hematopoiesis (lymphoblast, prolymphocyte and lymphocyte) are characterized by a very large, rounded, sometimes bean-shaped nucleus of a dense structure, occupying almost the entire cell. The cytoplasm is blue or blue in color and is located in a narrow strip around the nucleus. It is devoid of specific granularity, in connection with which lymphocytes, together with monocytes, are called agranulocytes. Normally, as is known, only mature leukocyte cells are found in the peripheral blood:

• segmented neutrophils, eosinophils and basophils;
• stab neutrophils (sometimes eosinophils);
• monocytes;
• lymphocytes.

Degenerative forms of leukocytes

In addition to the cells described above, in pneumonia, infections and purulent-inflammatory diseases, there are so-called pre-generative forms of leukocytes. The most common forms are the following:

1. Neutrophils with toxic granularity and vacuolization of the cytoplasm. Toxic granularity of neutrophils occurs as a result of cytoplasmic protein coagulation under the influence of an infectious or toxic agent. In these cases, in addition to the fine, delicate granularity characteristic of neutrophils, large coarse, basophilically stained granules and vacuoles appear in the cytoplasm. Toxic granularity and vacuolization of the cytoplasm of neutrophils and monocytes is often found in severe pneumonia, for example, in severe pneumococcal lobar pneumonia and other purulent-inflammatory diseases accompanied by severe intoxication.
2. Hypersegmented neutrophils, the nucleus of which consists of 6 or more segments, are found in B12-folate deficiency anemia, leukemia, as well as in some infections and purulent-inflammatory diseases, reflecting the so-called nuclear shift of neutrophils to the right.
3. Degenerative changes in lymphocytes in the form of a pycnotically altered nucleus, sometimes having a bilobed structure, and weak development or absence of cytoplasm
4. Atypical mononuclear cells are cells that combine some morphological features of lymphocytes and monocytes: they are larger than ordinary lymphocytes, but do not reach monocytes in size, although they contain a monocytic nucleus. In morphology, lymphomonocytes resemble blast cells and are often found in infectious mononucleosis.

Interpretation of results

Leukocyte formula in healthy people

In various pathological conditions, including pneumonia, the following can occur:

• change in the leukocyte formula (increase or decrease in any type of leukocytes);
• the appearance of various degenerative changes in the nucleus and cytoplasm of mature leukocyte cells (neutrophils, lymphocytes and monocytes);
• the appearance in the peripheral blood of young immature leukocytes.

For the correct interpretation of changes in the leukocyte formula, it is necessary to evaluate not only the percentages of different types of leukocytes, but also their absolute content in 1 liter of blood. This is due to the fact that the change in the percentage of certain types of leukocytes does not always correspond to their true increase or decrease. For example, with leukopenia due to a decrease in the number of neutrophils, a relative increase in the percentage of lymphocytes and monocytes can be detected in the blood, while their absolute number will actually be normal.

If, along with a percentage increase or decrease in certain types of leukocytes, there is a corresponding change in their absolute content in 1 liter of blood, they speak of their absolute change. An increase or decrease in the percentage of cells in their normal absolute content in the blood corresponds to the concept of a relative change.

Let us consider the diagnostic value of some changes in the leukocyte count, which are most common in clinical practice, including in patients with pneumonia.

When evaluating the diagnostic and prognostic significance of a neutrophilic shift, it is important to determine the percentage of immature and mature forms of neutrophils. To do this, the nuclear shift index of neutrophils is calculated - the ratio of the content of myelocytes, metamyelocytes and stab neutrophils to segmented ones.

Nuclear shift index = myelocytes + metamyelocytes + stab / segmented

Normally, the nuclear shift index is 0.05-0.1.

• A shift in the blood count to the left is an increase in the number of stab neutrophils in the peripheral blood and (less often) the appearance of a small number of immature granulocytes (metamyelocytes, myelocytes, and even single myeloblasts), which indicates a significant irritation of the bone marrow and acceleration of leukopoiesis. The nuclear shift index of neutrophils in this case exceeds 0.1.
• The shift of the blood formula to the right is an increase in the number of mature segmented neutrophils in the peripheral blood, the appearance of hypersegmented and a decrease or disappearance of stab neutrophils. The nuclear shift index is less than 0.05.

In most patients with pneumonia, acute infections, purulent-inflammatory and other diseases accompanied by neutrophilia, the shift of the blood formula to the left is limited only by an increase in the number of stab neutrophils (hyporegenerative nuclear shift), which, in combination with moderate leukocytosis, as a rule, indicates a relatively mild infection or limited purulent-inflammatory process and good body resistance.

In the severe course of the disease and the body's resistance is preserved, a shift in the blood formula to metamyelocytes, myelocytes and (less often) to myeloblasts (hyperregenerative nuclear shift to the left) is observed, which, in combination with high leukocytosis and neutrophilia, is referred to as a myeloid-type leukemoid reaction, since it resembles a blood picture in myeloid leukemia . These changes are usually accompanied by hypo- and aneosinophilia, relative lymphocytopenia and monocytopenia.

Neutrophilia with a degenerative nuclear shift to the left, which is manifested by an increase in immature forms of neutrophils and the appearance of degeneratively altered segmented neutrophils in the peripheral blood (toxic granularity, pycnosis of nuclei, vacuolization of the cytoplasm) is also observed in severe pneumonia. Purulent-inflammatory diseases and endogenous intoxications and indicates the inhibition of the functional activity of the bone marrow.

Neutrophilia with a pronounced shift of the blood formula to the left, combined with slight leukocytosis or leukopenia, as a rule, indicates a severe course of the pathological process and poor body resistance. Quite often such picture of blood is observed at persons of advanced and senile age and at the weakened and exhausted patients.

Neutrophilia with a nuclear shift to the right (an increase in segmented and hyperpigmented neutrophils, a decrease or disappearance of stab neutrophils), as a rule, indicates a good, adequate protective reaction of the bone marrow hematopoiesis to an infection or inflammatory process and a favorable course of the disease.

The severe course of many pneumonias, as well as infectious, generalized purulent-inflammatory, degenerative and other diseases, with preserved body resistance, is often accompanied by severe neutrophilia, leukocytosis and a hyperregenerative shift of the blood formula to the left.

The appearance in the peripheral blood of degenerative forms of neutrophils (toxic granularity, pycnosis of nuclei and other changes), as well as pronounced neutrophilia and a nuclear shift to the left, combined with slight leukocytosis or leukopenia, in most cases indicate inhibition of the functional activity of the bone marrow, a decrease in the body's resistance and are very unfavorable signs.

Neutropenia - a decrease in the number of neutrophils below 1.5 x 109 / l - indicates a functional or organic inhibition of bone marrow hematopoiesis or an intensive destruction of neutrophils under the influence of antibodies to leukocytes, circulating immune complexes or toxic factors (autoimmune diseases, tumors, aleukemic forms of leukemia, the effect some medicines, hypersplenism, etc.). It should also be borne in mind the possibility of a temporary redistribution of neutrophils within the vascular bed, which can be observed, for example, in shock. Neutropenia is usually combined with a decrease in the total number of leukocytes - leukopenia.

The most common causes of neutropenia are:

1. Infections: viral (influenza, measles, rubella, chickenpox, infectious hepatitis, AIDS), some bacterial (typhoid, paratyphoid, brucellosis), rickettsial (typhus), protozoal (malaria, toxoplasmosis).
2. Other acute and chronic infections and inflammatory diseases that are severe and / or acquire the character of generalized infections
3. The action of certain medications (cytostatics, sulfonamides, analgesics, anticonvulsants, antithyroid drugs, etc.).

Neutropenia, especially combined with a neutrophilic shift to the left, and developing against the background of purulent-inflammatory processes, for which neutrophilia is typical, indicates a significant decrease in the body's resistance and an unfavorable prognosis of the disease. Such a reaction of bone marrow hematopoiesis in patients with pneumonia is most characteristic of malnourished, debilitated patients and elderly and senile people.

Moderate eosinophilia often develops during the period of convalescence of patients with pneumonia and other acute infectious and inflammatory diseases (“scarlet dawn of recovery”). In these cases, eosinophilia is usually combined with a decrease in previously observed neutrophilia and leukocytosis.

Eosinopenia - a decrease or disappearance of eosinophils in the peripheral blood - is often detected in infectious and purulent-inflammatory diseases and, along with leukocytosis, neutrophilia and a nuclear shift in the blood formula to the left, is an important laboratory sign of an active inflammatory process and a normal (adequate) reaction of bone marrow hematopoiesis to inflammation .

Eosinopenia, detected in patients with pneumonia and purulent-inflammatory diseases, in combination with neutropenia, leukopenia and a shift in the blood formula to the left, as a rule, reflects a decrease in the body's resistance and is a very unfavorable prognostic sign.

Basophilia - an increase in the number of basophils in the blood - in clinical practice, including pneumonia, is quite rare. Among the diseases most often accompanied by basophilia, the following can be distinguished:

1. Myeloproliferative diseases (chronic myeloid leukemia, myelofibrosis with myeloid metaplasia, polycythemia vera - Wakez's disease);
2. Hypothyroidism (myxedema);
3. Lymphograiulomatosis;
4. Chronic hemolytic anemia.

The absence of basophils in the peripheral blood (basopenia) has no diagnostic value. It is sometimes detected in hyperthyroidism, acute infections, after taking corticosteroids.

Lymphocytosis - an increase in the number of lymphocytes in the peripheral blood. In clinical practice, relative lymphocytosis is more common, that is, an increase in the percentage of lymphocytes with a normal (or even somewhat reduced) absolute number. Relative lymphocytosis is detected in all diseases accompanied by absolute neutropenia and leukopenia, including viral infections (flu), purulent-inflammatory diseases that occur against the background of a decrease in body resistance and neutropenia, as well as typhoid fever, brucellosis, leishmaniasis, agranulocytosis, etc. .

The absolute increase in the number of lymphocytes in the blood is more than 3.5 x 109 / l (absolute lymphocytosis) is characteristic of a number of diseases:

1. Acute infections (including the so-called childhood infections: whooping cough, measles, rubella, chickenpox, scarlet fever, infectious mononucleosis, mumps, acute infectious lymphocytosis, acute viral hepatitis, cytomegalovirus infection, etc.).
2. Tuberculosis.
3. Hyperthyroidism.
4. Acute and chronic lymphocytic leukemia.
5. Lymphosarcoma.

Contrary to popular belief, lymphocytosis in purulent-inflammatory diseases and pneumonia cannot be considered as a reliable laboratory sign of a compensatory reaction of the immune system and the onset of recovery. Lymphocytopenia - a decrease in the number of lymphocytes in the peripheral blood. Relative lymphocytopenia is observed in such diseases and at such a stage in the development of the pathological process, which is characterized by an absolute increase in the number of neutrophils (neutrophilia): various infections, purulent-inflammatory diseases, pneumonia. Therefore, in most cases, such relative lymphocytopenia has no independent diagnostic and prognostic value.

Absolute lymphocytopenia with a decrease in the number of lymphocytes below 1.2 x 109/l may indicate insufficiency of the T-system of immunity (immunodeficiency) and requires a more thorough immunological blood test, including an assessment of humoral cellular immunity and phagocytic activity of leukocytes.

Monocytosis can also be relative and absolute.

Relative monocytosis is often found in diseases that occur with absolute neutropenia and leukopenia, and its independent diagnostic value in these cases is small.

Absolute monocytosis, detected in some infections and purulent-inflammatory processes, should be assessed, first of all, bearing in mind that the main functions of the monocyte-macrophage series are:

1. Protection against certain classes of microorganisms.
2. Interaction with antigens and lymphocytes at certain stages of the immune response.
3. Elimination of damaged or aged cells.

Absolute monocytosis occurs in the following diseases:

1. Some infections (infectious mononucleosis, subacute septic endocarditis, viral, fungal, rickettsial and protozoal infections).
2. Long-term purulent-inflammatory diseases.
3. Granulomatous diseases (active tuberculosis, brucellosis, sarcoidosis, ulcerative colitis, etc.).
4. Blood diseases: acute myeloid leukemia, chronic myeloid leukemia, multiple myeloma, lymphogranulomatosis, other lymphomas, aplastic anemia.

In the first three cases (infections, purulent-inflammatory diseases), absolute monocytosis may indicate the development of pronounced immune processes in the body.

Monocytonia - a decrease or even complete absence of monocytes in the peripheral blood - often develops in severe pneumonia, infectious and purulent-inflammatory diseases.

Leukemoid reactions are pathological reactions of the hematopoietic system, accompanied by the appearance of young immature leukocytes in the peripheral blood, which indicates a significant irritation of the bone marrow and an acceleration of leukopoiesis. In these cases, the blood picture outwardly resembles the changes detected in leukemia. Leukemoid reactions are more often combined with severe leukocytosis, although in more rare cases they can develop against the background of a normal number of leukocytes or even leukopenia.

There are leukemoid reactions 1) myeloid type, 2) lymphatic (or monocytic-lymphatic) type, 3) eosinophilic type.

Myeloid-type leukemoid reaction is accompanied by a shift in the blood count to metamyelocytes, myelocytes and myeloblasts and is observed in severe infectious, purulent-inflammatory, septic, degenerative and other diseases and intoxications, which are characterized by a hyperregenerative nuclear shift of neutrophils to the left. A particularly severe and prognostically unfavorable sign in these diseases is the combination of a leukemoid reaction with a normal or reduced number of leukocytes and neutrophils (leukopenia and neutropenia).

Erythrocyte sedimentation rate (ESR)

The definition of ESR is based on the property of erythrocytes to settle on the bottom of the vessel under the influence of gravity. For this purpose, the T.P. micromethod is usually used. Panchenkov. ESR is determined 1 hour after the start of the study by the size of the plasma column above the settled erythrocytes. Normal ESR in men is 2-10, and in women - 4-15 mm per hour.

The mechanism of agglomeration of erythrocytes and their sedimentation is extremely complex and depends on many factors, primarily on the qualitative and quantitative composition of blood plasma and on the physicochemical properties of the erythrocytes themselves.

As you know, the most common cause of an increase in ESR is an increase in the content of coarse proteins (fibrinogen, a-, beta- and gamma-globulins, paraproteins) in the plasma, as well as a decrease in the content of albumins. Coarsely dispersed proteins have a smaller negative charge. Being adsorbed on negatively charged erythrocytes, they reduce their surface charge and contribute to the convergence of erythrocytes and their faster agglomeration.

An increase in ESR is one of the characteristic laboratory signs of pneumonia, the direct cause of which is the accumulation in the blood of coarsely dispersed fractions of globulins (usually a-, beta- and gamma-fractions), fibrinogen and other proteins of the acute phase of inflammation. At the same time, there is a certain correlation between the severity of inflammation of the lung tissue and the degree of increase in ESR.

At the same time, it should be remembered that an increase in ESR is, although very sensitive, according to a non-specific hematological indicator, an increase in which can be associated not only with inflammation, but also with any pathological process leading to severe dysproteinemia (connective tissue diseases, hemoblastosis, tumors , anemia, tissue necrosis, liver and kidney disease, etc.).

On the other hand, in patients with pneumonia, the ESR may not be increased if at the same time there is a thickening of the blood (increased viscosity) or a decrease in pH (acidosis), which, as is known, causes a decrease in erythrocyte agglomeration.

In addition, in the early stages of some viral infections, there is also no increase in ESR, which can to some extent distort the results of the study in patients with viral-bacterial pneumonia.

Biochemical blood test for pneumonia

Evaluation of the results of biochemical blood tests in patients with pneumonia, especially in dynamics - in the course of the development of the disease, is of great diagnostic and prognostic value. Changes in various biochemical parameters, being in most cases nonspecific, make it possible to judge the nature and degree of disturbance of metabolic processes both in the whole organism and in individual organs. Comparison of this information with the clinical picture of the disease and the results of other laboratory and instrumental research methods makes it possible to assess the functional state liver, kidneys, pancreas, endocrine organs, hemostasis system, and often - to get an idea about the nature of the pathological process, the activity of inflammation and timely recognize a number of complications of pneumonia.

Protein and protein fractions

The determination of protein and protein fractions in patients with pneumonia is of particular importance, first of all, for assessing the activity of the inflammatory process. The concentration of proteins in the plasma of a healthy person ranges from 65 to 85 g / l. The main part of the total plasma protein (about 90%) is accounted for by albumins, globulins and fibrinogen.

Albumins are the most homogeneous fraction of simple proteins, almost exclusively synthesized in the liver. About 40% of albumin is in the plasma, and 60% in the interstitial fluid. The main functions of albumins are the maintenance of colloid-osmotic (oncotic) pressure, as well as participation in the transport of many endogenous and exogenous substances (free fatty acids, bilirubin, steroid hormones, magnesium ions, calcium, antibiotics, and others).

Serum globulins are represented by four fractions (a1, a2, beta and gamma), each of which is not homogeneous and contains several proteins that differ in their functions.

The composition of a1-globulins normally includes two proteins that have the greatest clinical significance:

• a1-antitrypsin, which is an inhibitor of a number of proteases (trypsin, chymotrypsin, kallikrein, plasmin);
• a1-glycoprotein involved in the transport of progesterone and testosterone, binding small amounts of these hormones.
• and 2-globulins are represented by the following proteins:
• a2-macroglobulin - an inhibitor of a number of proteolytic enzymes (trypsin, chymotrypsia, thrombin, plasmin, kallikrein), is synthesized outside the liver;
• haptoglobin - a protein that binds and transports free hemoglobin A to the cells of the reticuloendothelial system;
• ceruloplasmin - has oxidase activity and oxidizes ferrous iron to trivalent, which ensures its transport by transferrin;
• apoproteins A, B and C, which are part of lipoproteins.

The globulin fraction also contains several proteins:

• transferrin - a protein involved in the transport of ferric iron;
• hemopexin - a carrier of free heme and porphyrin, binds heme-containing chromoproteins (hemoglobin, myoglobia, catalase) and delivers them to liver RES cells;
• lipoproteins;
• part of immunoglobulins;
• some protein components of complement.

Gamma globulins are immunoglobulins that are characterized by the function of antibodies produced in the body in response to the introduction of various substances with antigenic activity; modern methods make it possible to isolate several classes of immunoglobulins (IgG, IgA, IgM, IgD and IgE).

Fibrinogen is an essential component of the blood coagulation system (factor I). It forms the basis of a blood clot in the form of a three-dimensional network in which blood cells linger.

Normal values ​​of protein fractions of blood serum (in%)

The albumin-globulin ratio (A/G) is normally 1.2-1.8.

Most often, there is an increase in the content of a1 and a2-fractions of globulins. This is due to the fact that a-globulins include the so-called acute phase proteins (a1-antitrypsin, o1-glycoprotein, a2-macroglobulin, haptoglobulin, ceruloplasmin, seromucoid, C-reactive protein), which naturally increase with any inflammatory process in the body. . In addition, an increase in the content of a-globulins is observed with significant tissue damage and decay (dystrophic, necrotic processes), accompanied by cell destruction and the release of tissue proteases, kallikrein, thrombin, plasmin, etc., which naturally leads to an increase in the content of their natural inhibitors (a1-antitrypsin, a1-glycoprotein, a2-macroglobulin, etc.). Tissue damage also leads to the release of pathological C-reactive protein, which is a product of cell decay and is part of the a1-fraction of globulins.

An increase in the fraction of beta-globulins is usually observed in acute and chronic diseases, accompanied by an increase in the content of immunoglobulins in the blood (usually simultaneously with an increase in the content of y-globulins), including infections, chronic inflammatory processes in the bronchi, cirrhosis of the liver, connective tissue diseases, malignant neoplasms, autoimmune and allergic diseases.

An increase in the y-globulin fraction is found in diseases accompanied by an intensification of immune processes, since the y-globulin fraction consists mainly of immunoglobulins: in chronic infections, chronic liver diseases (chronic hepatitis and cirrhosis of the liver), autoimmune diseases (including connective tissue diseases - RA, SLE, etc.), chronic allergic diseases (bronchial asthma, recurrent urticaria, drug disease, atopic dermatitis and eczema, etc.). An increase in the y-globulin fraction is also possible with pneumonia, especially a protracted course.

Acute phase proteins

In addition to the described changes in protein fractions, patients with pneumonia are characterized by an increase in the content of the so-called acute phase proteins of inflammation: fibrinogen, ceruloplasmin, haptoglobulin, a2-macroglobulin, C-reactive protein, etc., which also belong to nonspecific markers of the inflammatory process.

Glycoproteins

Among the diagnostically important carbohydrate-containing compounds are glycoproteins - proteins containing relatively short carbohydrate chains consisting of 10-20 monosaccharides. Their concentration in the blood also increases significantly during inflammatory processes and tissue damage (necrosis).

The composition of the carbohydrate components of glycoproteins, the quantitative determination of which underlies most diagnostic tests, includes:

1. hexoses (galactose, mannose, less often - glucose);
2. pentoses (xylose and arabinose);
3. deoxysugar (fucose and rhamnose);
4. amino sugars (acetylglucosamine, acetylgalactosamine);
5. sialic acids are derivatives of neuraminic acid (acetylneuraminic and glycolylneuraminic acids).

In clinical practice, methods for determining sialic acids and the total amount of hexoses associated with proteins are most widely used.

An important diagnostic value is also the definition of hexoses associated with the so-called seromucoids. Seromucoids are a special group of carbohydrate-containing proteins that differ from ordinary glycoproteins in their ability to dissolve well in perchloric acid. This last property of seromucoids makes it possible to identify them from other glycoproteins containing hexoses.

Normally, the total content of hexoses associated with plasma or serum proteins is 5.8-6.6 mmol / l. Of these, seromucoids account for 1.2-1.6 mmol / l. The concentration of sialic acids in the blood of a healthy person does not exceed 2.0-2.33 mmol/L. The content of total hexoses, seromucoid and sialic acids associated with proteins increases significantly in any inflammatory processes and tissue damage (pneumonia, myocardial infarction, tumors, etc.).

Lactate dehydrogenase (LDH)

Lactate dehydrogenase (LDH) (EC 1.1.1.27) is one of the most important cellular enzymes involved in the process of glycolysis, and catalyzes the reversible reduction reaction of pyruvic acid (pyruvate) to lactic acid (lactate).

As you know, pyruvate is the end product of glycolysis. Under aerobic conditions, pyruvate, undergoing oxidative decarboxylation, is converted to acetyl-CoA and then oxidized in the tricarboxylic acid cycle (Krebs cycle), releasing a significant amount of energy. Under anaerobic conditions, pyruvate is reduced to lactate (lactic acid). This last reaction is catalyzed by lactate dehydrogenase. The reaction is reversible: in the presence of O2, lactate is again oxidized to pyruvate.

With electrophoresis or chromatography, it is possible to detect 5 LDH isoenzymes that differ in their physicochemical properties. Two isoenzymes are of the greatest importance - LDH1 and LDH5. Most organs contain a complete set of LDH isoenzymes, including fractions LDH2, 3, 4.

Normally, LDH activity in blood serum does not exceed 0.8-4.0 mmol / h x l). Any damage to tissue cells containing a large amount of LDH, including damage observed during inflammation of the lungs, leads to an increase in the activity of LDH and its isoenzymes in the blood serum.

Nonspecific biochemical criteria of the inflammatory process in patients with pneumonia are:

• an increase in the content of alpha and beta globulins in the blood serum, and with a more significant activation of the immune system and / or a chronic process, an increase in the content of γ-globulins;
• an increase in the content of acute phase proteins in the blood: fibrinogen, ceruloplasmin, haptoglobulin, C-reactive protein, etc .;
• an increase in the content of total hexoses associated with proteins, seromucoid and sialic acids;
• an increase in the activity of lactate dehydrogenase (LDH) and its isoenzymes - LDH3.

Determination of sensitivity to antibiotics

The determination of sensitivity to antibiotics is based on the assessment of the growth of microorganisms cultivated on solid or liquid nutrient media in the presence of antibiotics. The simplest way is to inoculate a suspension of microorganisms of the isolated culture on the surface of a dense nutrient medium (agar) in Petri dishes, disks with antibiotics in standard concentrations are placed on the surface of the dishes and incubated at 37.5 ° C for 18 hours. The results are evaluated by measuring with a ruler diameter of the microbial growth inhibition zone.

More accurate data can be obtained using quantitative methods to determine the minimum inhibitory concentration (MIC) of antibiotics. For this purpose, a series of two-fold dilutions of antibiotics in a liquid nutrient medium (broth) is prepared and 0.2 ml of a suspension of the culture of the studied microorganisms is added at a concentration of 105-106 m.t./ml. All samples, including the control, not containing antibiotics, are incubated at 37.5°C for 24 hours. The minimum concentration of antibiotic in the last tube, in which a complete inhibition of culture growth was observed, corresponds to the MIC of the drug and reflects the degree of sensitivity of microorganisms to the antibiotic.

According to the degree of sensitivity to antibiotics, microorganisms are divided into three groups:

1. Sensitive - microorganisms, the growth of which is suppressed by the IPC, the corresponding concentration of the drug in the blood serum when using the usual therapeutic doses of the drug.
2. Moderately resistant - such strains of microorganisms, the IPC of which is achieved by prescribing the maximum therapeutic doses of the antibiotic.
3. Resistant microorganisms whose growth is not suppressed by the maximum allowable doses of drugs.

Such a determination of the degree of sensitivity to antibiotics is possible using quantitative methods of dilution in liquid nutrient media. However, there is a definite correlation between MIC values ​​and the size of microbial growth inhibition zones in the use of antibiotic paper discs, which justifies the use of this simple and convenient method for an approximate quantitative description of the degree of sensitivity.

Nevertheless, it should be remembered that the results of in vitro antibiotic susceptibility testing do not always correspond to the real clinical situation, especially with mixed infection, a decrease in the immunological reactivity of the body, difficulties that arise when trying to isolate the culture of the main pathogen, etc.

Formulation of the diagnosis

When formulating the diagnosis of pneumonia, it is necessary to reflect:

• etiological option;
• localization and prevalence of the inflammatory process (segment, lobe, one- or two-sided lesion);
• severity of pneumonia;
• the presence of complications;
• phase of the disease (peak, resolution, convalescence, protracted course);
• accompanying illnesses.

Examples of the formulation of the diagnosis

1. Pneumococcal lobar pneumonia in the lower lobe of the right lung, severe course, peak phase. Acute subcompensated respiratory failure.
2. Streptococcal pneumonia in 6, 8, 10 segments of the right lung, moderate course, peak phase. The initial stage of acute respiratory failure. Exudative pleurisy.

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Diagnosis of pneumonia in children

Laboratory diagnosis of pneumonia

Peripheral blood testing should be performed in all patients with suspected pneumonia. Leukocytosis more than 10-12x109/l and stab shift more than 10% indicate a high probability of bacterial pneumonia. With an established diagnosis of pneumonia, leukopenia less than 3x109/l or leukocytosis more than 25x109/l is considered unfavorable prognostic signs.

Biochemical analysis of blood and the study of the acid-base state of the blood are standard methods for examining children and adolescents with severe pneumonia. requiring hospitalization. Determine the activity of liver enzymes, the level of creatinine and urea, electrolytes.

The etiological diagnosis is established mainly in severe pneumonia. Perform blood cultures, which give a positive result in 10-40% of cases. Microbiological examination of sputum in pediatrics is not widely used due to the technical difficulties of sputum sampling in the first 7-10 years of life. But in cases of bronchoscopy, microbiological examination is used, the material for it is aspirates from the nasopharynx, tracheostomy and endotracheal tube. In addition, to identify the pathogen, a puncture of the pleural cavity and sowing of the punctate of the pleural contents are performed.

Serological research methods are also used to determine the etiology of the disease. The increase in titers of specific antibodies in paired sera taken during the acute period and the period of convalescence. may indicate a mycoplasmal or chlamydial etiology of pneumonia. Reliable methods also consider the detection of antigens by latex agglutination, counter immunoelectrophoresis, ELISA. PCR, etc. All these methods, however, take time, do not affect the choice of treatment tactics, and have only epidemiological significance.

Instrumental methods for diagnosing pneumonia

The "gold standard" for diagnosing pneumonia in children is an x-ray examination of the chest organs, which is considered a highly informative and specific diagnostic method (the specificity of the method is 92%). When analyzing radiographs, the following indicators are evaluated:

• size of lung infiltration and its prevalence;
• presence or absence of pleural effusion;
• the presence or absence of destruction of the lung parenchyma.

All these data help to determine the severity of the disease and choose the right antibiotic therapy. Subsequently, with a clear positive dynamics of the clinical manifestations of community-acquired pneumonia, there is no need for control radiography (when discharged from the hospital or when the child is treated at home). It is more expedient to carry out control radiography not earlier than 4-5 weeks after the onset of the disease.

X-ray examination in dynamics in the acute period of the disease is carried out only in the presence of progression of symptoms of lung damage or when signs of destruction and / or involvement of the pleura in the inflammatory process appear. In cases of a complicated course of pneumonia, a mandatory x-ray control is carried out before the patient is discharged from the hospital.

In case of nosocomial pneumonia, it must be remembered that if pneumonia develops 48 hours before death, then an x-ray examination may give a negative result. Such X-ray negative pneumonia (when radiography performed 5-48 hours before the death of the patient did not reveal pneumonic infiltration in the lungs) is observed in 15-30% of cases. The diagnosis is established only clinically on the basis of severe respiratory failure, weakened breathing; often there can be a short-term rise in temperature.

An X-ray study in dynamics in nosocomial pneumonia in the acute period of the disease is carried out with the progression of symptoms of lung damage or with the appearance of signs of destruction and / or involvement of the pleura in the inflammatory process. With a distinct positive dynamics of the clinical manifestations of pneumonia, control radiography is performed upon discharge from the hospital.

When assessing the condition of children previously hospitalized for any pathology and children with severe community-acquired pneumonia, special attention should be paid to the condition and effectiveness of the respiratory function, in particular, pulse oximetry readings. In severe pneumonia and nosocomial pneumonia, especially VAP, it is also necessary to monitor such indicators as respiratory rate, pulse rate, blood pressure, acid-base state, diuresis, and in children of the first six months of life - body weight.

Computed tomography (CT) is used, if necessary, in differential diagnosis, since CT has a 2-fold higher sensitivity than plain radiography in detecting infiltration foci in the lower and upper lobes of the lungs.

Fibrobronchoscopy and other invasive techniques are used to obtain material for microbiological examination in patients with severe immune disorders and in differential diagnosis.

Differential diagnosis of pneumonia in a child

When conducting differential diagnosis, it is necessary to take into account the age of the child, since at different age periods, pathological processes in the lungs have their own characteristics.

In infancy, the clinical picture of respiratory failure may be due to conditions such as aspiration, a foreign body in the bronchi, previously undiagnosed tracheoesophageal fistula, gastroesophageal reflux, malformations of the lungs (lobar emphysema), heart and large vessels, cystic fibrosis and a-antitrypsin deficiency. In children of the second or third years of life and at an older age (up to 6-7 years), Kartagener's syndrome should be excluded; hemosiderosis of the lungs; nonspecific alveolitis; selective IgA deficiency.

Differential diagnosis at this age should be based on the use (in addition to X-ray of the lungs and analysis of peripheral blood) endoscopic examination of the trachea and bronchi, lung scintigraphy, angiography, sweat and other tests for cystic fibrosis, determination of the concentration of a-antitrypsin, study of the immunogram of the blood and others. research.

At any age, it is necessary to exclude pulmonary tuberculosis. In the absence of positive dynamics of the process within 3-5 days (maximum - 7 days) of therapy, protracted course of community-acquired pneumonia, its resistance to ongoing therapy, it is necessary to expand the examination plan both to identify atypical pathogens (S. psittaci, Ps. aerugenozae, Leptospira, Coxiella burneti). and for the diagnosis of other lung diseases.

In patients with severe immunity defects, with the appearance of shortness of breath and focal infiltrative changes on the radiograph of the lungs, it is necessary to exclude the involvement of the lungs in the main pathological process (for example, with systemic diseases of the connective tissue), as well as lung damage as a consequence of the therapy (drug lung injury, radiation pneumonitis .d.).

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Differential diagnosis of pneumonia

Pulmonary tuberculosis

Regardless of the clinical variant of pneumonia and the form of pulmonary tuberculosis, when conducting differential diagnosis between these diseases, it is necessary, first of all, to use well-known methods for diagnosing pulmonary tuberculosis as a nosological unit.

Anamnesis data analysis

The following anamnestic data allow us to assume the presence of tuberculosis in a patient:

• the presence of tuberculosis in the patient's family;
• tuberculosis of any localization transferred by the patient earlier;
• clarification of the course of the disease. Acute onset and severe course are observed in acute miliary pulmonary tuberculosis and caseous pneumonia; in other forms of tuberculosis, the onset of the disease is usually gradual, often not noticeable at all. Acute lobar pneumonia has an acute onset, focal pneumonia begins gradually, but the duration of the initial period, of course, is much less than with pulmonary tuberculosis;
• information about past illnesses. Diseases such as exudative pleurisy, often recurring fibrinous (dry) pleurisy, prolonged low-grade fever of unknown origin and unexplained malaise, sweating, weight loss, prolonged cough (especially if the patient does not smoke) with hemoptysis may be manifestations of pulmonary tuberculosis.

Analysis of external examination data of patients

Previously transferred tuberculosis may be indicated by irregularly shaped scars in the region of the previously affected cervical lymph nodes, and kyphosis, which once had a place in the spinal tuberculosis.

Rapidly developing severe intoxication and a serious condition of the patient are more characteristic of lobar or total pneumonia and are not characteristic of tuberculosis, with the exception of acute miliary tuberculosis and caseous pneumonia.

Analysis of physical data obtained in the study of the lungs

Unfortunately, there are no physical symptoms that are absolutely pathognomonic for pulmonary tuberculosis. Data such as changes in voice trembling, bronchophony, bronchial breathing, crepitus, wet and dry rales, pleural friction noise can be observed both in pulmonary tuberculosis and in nonspecific lung diseases, including pneumonia.

Nevertheless, the following features of physical data characteristic of pulmonary tuberculosis may have a certain diagnostic value:

• localization of pathological percussion and auscultatory phenomena mainly in the upper sections of the lungs (of course, this is not an absolute rule);
• the paucity of physical data in comparison with the data of X-ray examination (the old doctors' aphorism "little is heard, but much is seen in pulmonary tuberculosis and a lot is heard, but little is seen in non-tuberculous pneumonia"). Of course, this pattern does not apply to all forms of tuberculosis, but can be observed with focal, miliary tuberculosis, tuberculoma.

Tuberculin testing

The staging of tuberculin tests (tuberculin diagnostics) is based on the determination of tuberculin allergy - the increased sensitivity of the body to tuberculin, which occurred as a result of infection with virulent mycobacteria of tuberculosis or BCG vaccination.

The most commonly used intradermal Mantoux test, while 0.1 ml of tuberculin is injected into the skin of the inner surface of the middle third of the forearm. The results of the test are evaluated after 72 hours by measuring the diameter of the papule using a transparent millimeter ruler. Register the transverse (with respect to the axis of the hand) diameter of the papule; the reaction is considered negative with a papule diameter of 0 to 1 mm, doubtful - with a diameter of 2-4 mm, positive - with a diameter of 5 mm or more, hyperergic - with a diameter of 17 mm or more in children and adolescents and 21 mm or more - in adults . Vesicular-necrotic reactions also belong to hyperergic reactions, regardless of the size of the infiltrate.

A positive and especially hyperergic tuberculin test may indicate the presence of pulmonary tuberculosis. However, the final diagnosis of pulmonary tuberculosis is made only on the basis of a comprehensive clinical, laboratory and radiological examination of the patient, while, of course, the results of tuberculin tests are also taken into account.

Microbiological diagnosis of tuberculosis

Determination of Mycobacterium tuberculosis in sputum, bronchial washings, in pleural exudate is the most important method for diagnosing tuberculosis. Classical microbiological methods are used: bacterioscopy, cultural examination or inoculation, biological test on laboratory animals susceptible to tuberculosis infection.

Sputum analysis is one of the main and most common methods. To increase the sensitivity of the method, the flotation method is used, in which mycobacteria are removed from an aqueous suspension of sputum using liquids with a relative density less than that of water (xylene, toluene, gasoline, benzene). At the same time, the frequency of detection of mycobacteria increases by at least 10% compared with conventional microscopy.

Smears are prepared from native sputum. Coloring is carried out by the Ziehl-Neelson method. Mycobacteria are found in the preparation in the form of thin straight or slightly curved bright red rods.

In recent years, the method of luminescence microscopy has been used. The method is based on the ability of lipids of mycobacteria to perceive luminescent dyes and then glow when irradiated with ultraviolet rays. Mycobacterium tuberculosis under fluorescent microscopy gives a bright red or luminescent yellow glow on a green background (depending on the type of dye). Fluorescent microscopy significantly increases the efficiency of the bacterioscopic method for detecting Mycobacterium tuberculosis.

The seeding method (cultural method for detecting Mycobacterium tuberculosis) is more sensitive than bacterioscopic. It detects Mycobacterium tuberculosis in sputum in the presence of several tens of viable individuals in 1 liter. For the cultivation of Mycobacterium tuberculosis, various nutrient media are used. As a standard medium for the primary isolation of the pathogen, WHO experts recommend Lowenstein-Jensen medium (dense egg medium), on which a good growth of Mycobacterium tuberculosis is obtained 15-25 days after sowing bacterioscopically positive material.

When sowing bacterioscopically negative material (sputum) on dense nutrient media, the average duration of growth of mycobacteria is 20-46 days, however, individual strains can grow up to 60-90 days. That is why sputum cultures should be incubated for at least 3 months. Then a microscopy of a smear from the grown colonies, stained according to Ziehl-Neelsen, is performed. Mycobacterium tuberculosis are found as bright red or dark red rods.

A biological sample is the most sensitive method for detecting Mycobacterium tuberculosis. It is used when bacterioscopy and sputum culture are negative, but tuberculosis is still suspected. The test consists in the introduction of specially processed sputum of the patient to the guinea pig. Then the mumps is slaughtered after 3 months and, with a positive result of the biological test, morphological signs of tuberculosis are found in the organs and tissues. During the autopsy, smears are made from the organs for bacterioscopic studies. In the absence of macroscopic signs of tuberculosis in the organs, inoculation is taken from the lymph nodes, spleen, liver, lungs and specially processed material on solid nutrient media.

The biological method, due to its complexity, is used relatively rarely.

In the diagnosis of pulmonary tuberculosis, the leading role belongs to X-ray methods of research. L. I. Dmitrieva (1996) suggests using them in the following way:

• obligatory x-ray diagnostic minimum (large-frame fluorography, plain radiography);
• in-depth x-ray examination (radiography in two mutually perpendicular projections; fluoroscopy; standard tomography);
• additional x-ray examination (various methods of radiography and tomography, including computed and magnetic resonance imaging).

Characteristic radiographic manifestations of individual forms of pulmonary tuberculosis are presented below.

Focal pulmonary tuberculosis

Focal pulmonary tuberculosis is a clinical form characterized by a limited inflammatory process (foci size is about 10 mm) and an asymptomatic clinical course. The main clinical features of focal pulmonary tuberculosis are as follows:

• long chronic undulating course with a change in phases of exacerbation and remission. For acute pneumonia, this course is not typical;
• the absence of vivid clinical manifestations even in the acute phase, and even more so in the compaction phase; with pneumonia, as a rule, the symptom of intoxication is pronounced significantly, especially with lobar pneumonia;
• characterized by prolonged cough without or with the release of a small amount of sputum (even if the patient is not a smoker);
• listening to fine bubbling rales in a limited area of ​​\u200b\u200bthe lung and, as a rule, after coughing;
• typical x-ray picture.

Radiological manifestations of focal pulmonary tuberculosis can be divided into three main groups:

• fresh forms are distinguished by unsharply defined foci of various shapes and sizes, sometimes merging against the background of pronounced lymphangitis;
• subacute forms are characterized by more sharply defined foci due to pronounced productive changes;
• fibrous-indurative changes with a predominance of linear strands over focal shadows.

With an exacerbation of focal tuberculosis, a zone of perifocal inflammation appears around the old foci and the development of new foci against the background of dense old foci is possible.

Infiltrative pulmonary tuberculosis

Infiltrative pulmonary tuberculosis is a clinical form characterized by a predominantly exudative type of inflammatory process with a tendency to rapid formation of caseous necrosis and destruction.

In size, tuberculous infiltrates are small (with a diameter of 1.5 to 3 cm), medium (from 3 to 5 cm) and large (more than 5 cm).

Clinical symptoms in infiltrative pulmonary tuberculosis are determined by the size of the lesion and the phase of the process.

The following clinical and radiological variants of infiltrative pulmonary tuberculosis are distinguished:

• cloud-like variant - characterized by a gentle, non-intense homogeneous shadow with fuzzy contours. In this case, rapid formation of decay and a fresh cavity is possible;
• round variant - appears as a rounded homogeneous low-intensity shadow with clear contours, the shadow diameter is more than 10 mm;
• lobitis - an infiltrative process affects the entire lobe, the shadow is inhomogeneous with the presence of decay cavities;
• periscissuritis - an extensive infiltrate, localized at the interlobar fissures and often causing the development of interlobar pleurisy, while the shadow on the one hand has a clear contour, on the other, its outlines are blurred;
• lobular variant - characterized by an inhomogeneous shadow formed as a result of the merger of large and small foci.

It is very difficult to differentiate between infiltrative pulmonary tuberculosis and acute pneumonia according to clinical signs, since there is a great similarity in the clinical manifestations of both of these diseases. As a rule, infiltrative tuberculosis, like acute pneumonia, occurs with a high body temperature, severe symptoms of intoxication, physical data are also similar. However, unlike pneumonia, hemoptysis is much more common in infiltrative tuberculosis. Very rarely, tuberculous infiltrate is asymptomatic or oligosymptomatic. In the diagnosis of infiltrative pulmonary tuberculosis, the leading role is played by X-ray examination of the lungs, a sharply positive tuberculin test, the determination of mycobacteria in sputum, and a clear positive effect of anti-tuberculosis therapy.

In addition, it should be taken into account that all clinical and radiological variants of infiltrative tuberculosis are characterized not only by the presence of an infiltrative shadow, but also by bronchogenic seeding in the form of fresh foci both in the lung, which has an infiltrate, and in the second lung. Quite often, with a tuberculous infiltrate, there is a "path" that goes from the infiltrate to the root of the lung, due to inflammatory peribronchial and perivascular changes (this is clearly visible on x-rays). Finally, it should be taken into account that, despite the fact that tuberculous infiltrate can be located in any part of the lung, it is most often localized in the region of the second bronchopulmonary segment and on the anterior radiograph is most often detected in the lateral zone of the subclavian region.

Caseous pneumonia

Caseous pneumonia is a clinical form of pulmonary tuberculosis, characterized by pronounced exudative inflammation of the entire lobe of the lung or most of it, which is quickly replaced by caseous-necrotic changes ("curdled" decay) followed by the formation of cavities. The course of caseous pneumonia is severe.

Miliary tuberculosis of the lungs

Miliary pulmonary tuberculosis is a dissemination of the tuberculosis process with the formation of small foci (1-2 mm) with a predominantly productive reaction, although caseous-necrotic changes are also possible. The disease begins acutely, body temperature rises to 39-40 ° C, intoxication syndrome is pronounced, patients are concerned about severe weakness, sweating (debilitating night sweats are possible), anorexia, weight loss, shortness of breath, persistent dry cough. With percussion of the lungs, there are no significant changes in percussion sound, with auscultation of the lungs, a small amount of dry rales may be heard due to the development of bronchiolitis. Thus, there is a certain similarity in the clinical manifestations of severe pneumonia and miliary pulmonary tuberculosis.

Disseminated pulmonary tuberculosis

Disseminated pulmonary tuberculosis is a clinical form characterized by the formation of many tuberculosis foci. Along the course, acute, subacute and chronic forms of disseminated pulmonary tuberculosis are distinguished. Acute and subacute forms are characterized by a severe course, patients have a high body temperature, chills, night sweats, a very pronounced intoxication syndrome, a cough, usually dry, less often with sputum. Severe dyspnea may develop. On auscultation of the lungs, small bubbling rales, crepitus in the upper and middle sections can be heard. The main method of diagnosis is radiological.

In acute disseminated tuberculosis in the lungs, focal shadows are determined, evenly distributed from the tops to the diaphragm - a picture of dense dissemination of small and medium-sized soft foci.

In subacute disseminated tuberculosis, the appearance of larger soft foci that merge with each other is characteristic. The foci have a tendency to decay, the rapid formation of caverns.

Chronic disseminated pulmonary tuberculosis usually develops imperceptibly, its clinical course is long, periodic dissemination of the process in the lungs may not give a clear clinical picture or proceed under the guise of pneumonia, exacerbation of chronic bronchitis. Often develops fibrinous or exudative pleurisy. Physical data in chronic disseminated pulmonary tuberculosis are scarce: a shortening of percussion sound can be detected, mainly in the upper parts of the lungs, hard vesicular breathing can be heard under areas of dullness, sometimes small bubbling or single dry rales (due to bronchial damage). Chronic disseminated pulmonary tuberculosis, both acute and subacute, can be complicated by decay and cavern formation. In this case, a tetrad of symptoms is characteristic: cough with sputum, hemoptysis, moist rales, Mycobacterium tuberculosis in sputum.

The progression of the process in chronic disseminated pulmonary tuberculosis leads to increased development of fibrosis and cirrhosis of the lungs.

Thus, disseminated pulmonary tuberculosis is quite difficult to distinguish from pneumonia. The decisive role in the diagnosis belongs to the X-ray method of investigation.

The main radiographic signs of disseminated pulmonary tuberculosis are (M. N. Lomako, 1978):

• bilateral lesion;
• polymorphism of focal shadows;
• alternation of well-defined lesions with fresh, poorly contoured lesions;
• localization of foci in the upper posterior costal sections (segments 1-2);
• different sizes of foci in different parts of the lungs: in the upper parts of the foci are larger, with clear contours and even the presence of calcareous inclusions; in the lower sections, smaller foci with more blurred contours;
• symmetrical arrangement of foci in both lungs in acute, asymmetric - in chronic disseminated pulmonary tuberculosis;
• the appearance of decay cavities with the progression of the process;
• progressive development of fibrosis and cirrhosis.

Differential diagnosis of pneumonia, pulmonary tuberculoma, cavernous and fibrous-cavernous pulmonary tuberculosis is not difficult due to the fact that these forms of tuberculosis have clear radiographic manifestations.

Tuberculoma is a cheesy-necrotic focus of a rounded shape, more than 1 cm in diameter, isolated and encapsulated by connective tissue.

In radiographic imaging, tuberculoma looks like a well-defined formation of a homogeneous or heterogeneous structure against the background of an intact lung. It is localized mainly in 1-2, 6 segments. Its shape is rounded, the edges are even. Most of the tuberculoma has a homogeneous structure. However, in some cases, its structure is heterogeneous, which is due to calcifications, foci of enlightenment, fibrous changes.

The most important differential diagnostic sign, not characteristic of pneumonia, is the presence of a double path in tuberculoma, which goes from tuberculoma to the root of the lung. This path is due to compacted peribronchial and perivascular infiltration. Quite often around a tuberculoma the capsule comes to light. Focal shadows can be found in the lung tissue around the tuberculoma. During the period of exacerbation of the tuberculous process, the x-ray image of tuberculoma is less clear than in the remission phase, even a focus of decay may be outlined. With the progressive course of tuberculoma, with the development of communication between it and the draining bronchus, mycobacterium tuberculosis may appear in the sputum.

Tuberculoma is sometimes difficult to distinguish from peripheral lung cancer. The most reliable method for diagnosing tuberculoma is bronchoscopy with biopsy followed by cytological and bacteriological examination.

Exudative pleurisy

The need for differential diagnosis of pneumonia with exudative pleurisy is due to a certain similarity in the symptoms of both diseases - the presence of shortness of breath, symptoms of intoxication, fever, dull percussion sound on the side of the lesion. The main distinguishing features are the following:

• a significantly more pronounced lag in breathing of the corresponding half of the chest with exudative pleurisy than with pneumonia;
• greater intensity of dull sound during percussion with exudative pleurisy than with lobar pneumonia. The dullness of the percussion sound with exudative pleurisy is considered absolute (“femoral”), it increases significantly downward, with percussion, the finger-plessimeter seems to feel resistance. With pneumonia, the intensity of percussion sound is less;
• the absence of auscultatory phenomena over the area of ​​dullness (there are no vesicular and bronchial breathing, voice trembling, bronchophony);
• intense dense homogeneous blackout with an upper oblique border on x-ray examination of the lungs, mediastinal shift to the healthy side;
• detection of fluid in the pleural cavity using ultrasound and pleural puncture.

Lung infarction

Pulmonary infarction occurs due to pulmonary embolism. The main features that distinguish it from pneumonia are:

• the appearance at the beginning of the disease of intense pain in the chest and shortness of breath, then - an increase in body temperature; with lobar pneumonia, the relationship of pain and fever is reversed: as a rule, there is a sudden increase in body temperature, chills; after that, there is pain in the chest, sometimes with pneumonia, a simultaneous increase in body temperature and pain in the chest is possible;
• the absence of severe intoxication at the onset of pulmonary embolism;
• hemoptysis is a common sign of a lung infarction, however, this can also be observed with pneumonia, but with a lung infarction, almost pure scarlet blood is released, and with pneumonia, mucopurulent sputum is coughed up with an admixture of blood (or “rusty sputum”);
• a smaller area of ​​lung damage (usually less than the size of the lobe) in contrast, for example, to the lobar lesion in pneumococcal pneumonia;
• a sharp decrease in the accumulation of the isotope in the infarction zone (due to a sharp violation of capillary blood flow) during radioisotope scanning of the lungs;
• characteristic ECG changes that suddenly appear - deviation of the electrical axis of the heart to the right, overload of the right atrium (high peaked prong Pvo II and III standard leads, in lead aVF), rotation of the heart around the longitudinal axis clockwise by the right ventricle forward (appearance of deep prong 5 in all chest leads). These ECG changes can also be observed in acute lobar pneumonia, but they are much less pronounced and are less common;
• the presence of thrombophlebitis of the veins of the lower extremities;
• characteristic x-ray changes - bulging of the a.pulmonalis cone, the blackout focus has the shape of a strip, less often a triangle with an apex directed towards the root of the lung.

Lungs' cancer

Lung cancer is a common disease. From 1985 to 2000, the number of patients with lung cancer will increase by 44%, and mortality - by 34.4%. The following methods are used to diagnose lung cancer.

Anamnesis data analysis

Lung cancer is more common in men, especially those over the age of 50. As a rule, they abuse smoking for a long time. Many patients have occupational hazards that contribute to the development of lung cancer: work with carcinogenic chemicals, nickel, cobalt, chromium compounds, iron oxides, sulfur compounds, radioactive substances, asbestos, radon, etc. The appearance of such symptoms is of great importance in the diagnosis of lung cancer as a persistent cough, a change in the timbre of the voice, the appearance of blood in the sputum, fever, lack of appetite, weight loss, chest pain. The significance of these anamnestic data increases even more if they are combined with a deformity or fuzziness of the root of the lungs that was first detected on an X-ray examination.

X-ray examination of the lungs

Peripheral lung cancer develops from the epithelium of the small bronchi or from the epithelium of the alveoli and can be located in any area (segment) of the lung. However, it is most often localized in the anterior segments of the upper lobes of the lungs.

Radiological manifestations of peripheral cancer largely depend on the size of the tumor. Radiological signs of peripheral lung cancer can be characterized as follows:

• a tumor of a small size (up to 1-2 cm in diameter), as a rule, manifests itself as a focus of darkening of an irregular round, polygonal shape; cancer of medium and large sizes has a more regular spherical shape;
• the intensity of the shadow of a cancerous tumor depends on its size. With a node diameter of up to 2 cm, the shadow has a low intensity, with a larger tumor diameter, its intensity increases significantly;
• very often the shadow of the tumor has a non-homogeneous character, which is due to the uneven growth of the tumor, the presence of several tumor nodules in it. This is especially noticeable in large tumors;
• contours of tumor shading depend on the phase of tumor development. The tumor up to 2 cm in size has an irregular polygonal shape and fuzzy contours. With tumor sizes up to 2.5-3 cm, the darkening has a spherical shape, the contours become radiant. With a size of 3-3.5 cm in diameter, the contours of the tumor become clearer, however, with further growth of peripheral cancer, the clarity of the contours disappears, the tuberosity of the tumor is clearly visible, sometimes decay cavities are determined in it;
• Riegler's symptom is characteristic - the presence of a cut along the contour of the tumor, which is due to the uneven growth of cancer;
• quite often, with peripheral lung cancer, a “path” to the root of the lung is visible, due to lymphangitis, peribronchial and perivascular tumor growth;
• x-ray examination in dynamics reveals progressive tumor growth. According to V. A. Normantovich (1998), in 37% of patients, doubling of the tumor occurs within 17-80 days; in 43% of patients - 81-160 days, in 20% of cases - 161-256 days;
• in advanced cases, the tumor compresses the corresponding bronchus, and atelectasis of the lobe of the lung develops.

In more detail, radiological signs of cancer and compression of the bronchus are detected using X-ray tomography and computed tomography of the lung.

In the differential diagnosis of acute pneumonia and peripheral lung cancer, the following circumstances must be taken into account:

• in acute pneumonia, under the influence of rational antibiotic therapy, a positive trend appears quite quickly - a decrease in severity and then the complete disappearance of the blackout focus; in cancer, such dynamics is not observed;
• acute pneumonia is characterized by a positive symptom of Fleischner - good visibility of small bronchi against the background of blackout; this sign is not observed in lung cancer;

Central cancer of the upper lobe and middle lobe bronchi is manifested by darkening of the entire lobe or segment with a decrease in the volume of the lobe of the lung. With X-ray tomography, a symptom of the stump of the lobar bronchus is determined. Cancer of the main bronchus is characterized by varying severity of its stenosis up to complete stenosis with the development of atelectasis of the entire lobe of the lung. Stenosis of large bronchi is well detected by X-ray tomography and computed tomography.

An important diagnostic method is a bronchographic examination, which reveals a break (“amputation”) of the bronchus when its lumen is blocked by a tumor.

Bronchoscopy

Bronchoscopy with multiple biopsy of the bronchial mucosa is of great importance in the diagnosis of lung cancer. During bronchoscopy, direct signs of lung cancer can be detected: endobronchial, endophytic or exophytic tumor growth, infiltrative changes in the bronchial wall. A tumor growing peribronchially manifests itself by indirect signs: protrusion, rigidity of the bronchus wall, friability of the mucous membrane, indistinct pattern of the cartilage rings of the lobar and segmental bronchi. Along with a biopsy of the bronchial mucosa, a bronchial lavage is performed, followed by a cytological examination of the lavage.

In 1982, Kinsley et al. described the method of fibrobronchoscopy with simultaneous ultraviolet irradiation of the bronchial mucosa. The method is based on the fact that bronchogenic cancer cells have the ability to selectively accumulate a hematoporphyrin derivative compared to healthy tissues and then fluoresce in ultraviolet rays. When using this technique, the fiber bronchoscope is supplied with a special source of ultraviolet radiation, a light guide, a filter and a focused image intensifier.

In some cases, during bronchoscopy, a transbronchial puncture biopsy of a lymph node suspicious in terms of metastasis is performed.

Cytological examination of sputum

It is necessary to test sputum for cancer cells at least 5 times. Cancer cells can be detected in sputum in 50-85% of patients with central and 30-60% of patients with peripheral lung cancer.

Cytological examination of pleural exudate

The appearance of exudative pleurisy in lung cancer indicates a far advanced tumor process. The pleural fluid in this case often has a hemorrhagic character, and its cytological examination reveals tumor cells.

Needle biopsy of palpable peripheral lymph nodes

Palpable peripheral lymph nodes (cervical, axillary, etc.) indicate lung cancer metastasis. Puncture biopsy of these lymph nodes provides verification of cancer metastasis in 60-70% of patients.

Immunological diagnostic methods

Immunological methods for diagnosing cancer have not yet received wide clinical application. However, according to the literature data, in the complex diagnosis of lung cancer, the detection of tumor markers in the blood, such as cancer-embryonic antigen, tissue polypeptide antigen, and lipid-bound sialic acids, may have a certain diagnostic value. The nonspecificity of these tumor markers should be taken into account; they can be detected in the blood in cancer of other organs (liver, stomach, etc.).

Transthoracic puncture

Transthoracic puncture is performed under X-ray television control and is the main method for verifying the diagnosis of peripheral cancer, confirming the diagnosis in 65-70% of cases.

Acute appendicitis

The need for differential diagnosis of acute appendicitis and pneumonia arises when it is localized in the lower lobe of the right lung. It is more often seen in children. Right-sided lower lobe pneumonia is often accompanied by pain and muscle tension in the right half of the abdomen, including in the right iliac region.

The main differential diagnostic differences between right-sided lower lobe pneumonia and acute appendicitis are as follows:

• with pneumonia, pain in the right iliac region does not increase when moving the hand deeper into the palpation of the abdomen; in acute appendicitis - the pain increases sharply, while the tension of the abdominal muscles also increases;
• in case of pneumonia, the pains are aggravated by breathing; in case of acute appendicitis, this connection is not typical or is not very pronounced; however, when coughing, the pain in the abdomen increases both in pneumonia and in acute appendicitis;
• in acute appendicitis, the temperature in the rectum is significantly higher than the temperature in the axillary region (the difference exceeds GS); in acute pneumonia, there is no such pattern;
• careful percussion and auscultation, x-ray examination of the lungs reveal the symptoms of acute pneumonia in the lower lobe of the right lung, which is the main criterion for differential diagnosis.

Cardiogenic pulmonary edema

The need for differential diagnosis of pneumonia and cardiogenic pulmonary edema (“congestive lung”) is explained by the presence of similar symptoms: cough with sputum (sometimes mixed with blood), shortness of breath, crepitus and fine bubbling rales in the lower parts of the lungs. Differential diagnostic differences are the following circumstances:

• the presence in patients with "congestive lungs" of symptoms of decompensated cardiac diseases (heart defects, postinfarction cardiosclerosis, severe arterial hypertension, diffuse myocarditis, exudative pericarditis, etc.);
• with "congestive lungs", as a rule, an increase in the size of the heart is detected, atrial fibrillation is more often detected, episodes of cardiac asthma and pulmonary edema are observed (the clinic of these conditions is described in the chapter "Acute circulatory failure");
• pulmonary edema almost always proceeds as a bilateral process, with auscultation of the lungs, crepitus and fine bubbling rales are heard in the lower sections of both lungs;
• X-ray changes in the lungs with congestion depend on the severity of the congestive process. At the stage of interstitial edema, an increase and deformation of the pulmonary pattern are revealed, due to the shadows of the longitudinal projections of crowded small vessels. With further progression of congestion and filling of the alveoli with transudate, bilateral darkening (often rounded) without clear boundaries appears, mainly in the medial areas of the middle and lower fields. With a significantly pronounced stagnation, an increase in the roots of the lungs is determined - they take the form of a butterfly;
• congestion in the lungs develops, as a rule, against the background of other clinical manifestations of circulatory failure (pronounced peripheral edema, ascites, enlarged painful liver);
• in the absence of concomitant pneumonia, stagnation in the lungs is not accompanied by pronounced laboratory signs of inflammation;
• congestive radiograph changes are significantly reduced and may even disappear completely after successful treatment of heart failure;
• sometimes in the sputum of patients with congestion in the lungs, cells of the alveolar epithelium are found, the protoplasm of which contains in excess phagocytosed grains of the hemoglobin derivative - hemosiderin.

The above signs make it possible to distinguish pneumonia from congestion in the lungs. However, it should be noted that pneumonia can develop against the background of congestion in the lungs. In this case, an asymmetric blackout is detected radiographically, most often in the lower lobe of the right lung, and laboratory signs of an inflammatory process appear.

Pneumonitis in systemic vasculitis and diffuse connective tissue diseases

With systemic vasculitis and diffuse diseases of the connective tissue, focal opacities in the lower parts of the lungs or peribronchial, perivascular infiltration, increased pulmonary pattern may be observed. In differential diagnosis with pneumonia, attention should be paid to the characteristic clinical manifestations of systemic vasculitis and systemic connective tissue diseases (systemic lesions, articular syndrome, as a rule, involvement of the kidneys in the pathological process, skin erythematous, hemorrhagic rashes, etc.), relevant laboratory manifestations, inefficiency antibiotic therapy and the positive effect of treatment with glucocorticosteroids.

Etiological diagnosis

Currently, the problem of timely and successful etiological diagnosis has become extremely relevant. Accurate etiological diagnosis is the key to correct and successful treatment of pneumonia.

The main methods for establishing the etiological diagnosis of pneumonia are:

• Careful analysis of the clinical, radiological and laboratory features of pneumonia, depending on its etiology.
• Microbiological examination of sputum, sometimes bronchial lavage, pleural effusion with a quantitative assessment of the content of microflora. Sputum should be collected in a sterile container after pre-rinsing the mouth. To increase the effectiveness of the study, it is advisable to first process the sputum according to the Mulder method. To do this, a purulent piece of sputum is taken and thoroughly washed in a sterile isotonic sodium chloride solution sequentially in three Petri dishes for 1 minute each. This helps to remove mucus containing the microflora of the upper respiratory tract and oral cavity from the surface of the sputum lump. It is advisable to take at least three lumps from different parts of the sputum. After that, sputum is cultured on elective biological media. The number of microbial bodies in 1 ml of sputum is also counted.

The causative agents of pneumonia in this patient are those microorganisms that are sown from sputum in the amount of 1,000,000 or more microbial bodies per 1 ml.

Simultaneously with sputum culture on elective biological media, sputum smears are made, followed by bacterioscopy. One smear is stained according to the Romanovsky-Giemsa method for cytological analysis (the type and number of leukocytes, the presence of bronchial, alveolar epithelium, erythrocytes, atypical cells, etc.) are determined. The second smear is stained according to Gram and the abundance of microflora, the presence of gram-positive and gram-negative microorganisms, their intra- or extracellular localization are assessed. But first it is necessary to establish the belonging of the preparations to sputum, and not to the oral mucosa. The criteria for belonging to sputum of Gram-stained preparations are:

• the number of epithelial cells, the main source of which is the oropharynx, is less than 10 for the total number of cells counted;
• the predominance of neutrophilic leukocytes over epithelial cells;
• the predominance of microorganisms of one morphological type. Bacterioscopy of Gram-stained sputum smears allows us to tentatively assume the causative agent of pneumonia. So, at detection of gram-positive diplococci it is necessary to think of a pneumococcus; chains of gram-positive cocci are characteristic of streptococcus, clusters of gram-positive cocci are characteristic of staphylococcus; short gram-negative rods - for Haemophilus influenzae; in addition, gram-negative microorganisms include moraxella, neisseria, klebsiella, E. coli.

Immunological research. Immunological methods that allow to verify the causative agent of pneumonia include the detection of bacterial agents using immune sera in the counter immunoelectrophoresis reaction; determination of titers of specific antibodies (using enzyme immunoassay, indirect hemagglutination reaction, complement fixation reaction). The role of determining specific antibodies in the blood serum especially increases when using the paired sera method (a significant increase in antibody titer during a second study after 10-14 days compared to the titers obtained at the onset of the disease).

ilive.com.ua

Viral pneumonia - causes, symptoms, diagnosis and treatment

Viral pneumonia is an inflammation of the lung tissue caused by viruses. It often occurs in children, in adults it has a mixed character - viral and bacterial. The virus negatively affects the immune system, because of this, a bacterial infection can join the virus. Such pneumonia is dangerous for young children, the elderly, and those who suffer from lung pathology. What to do in this situation? What are the symptoms of viral pneumonia? What treatment is effective?

Symptoms of viral pneumonia

The symptoms are similar to a respiratory viral infection or the flu:

1. Body temperature rises.

2. The appearance of an unproductive cough.

3. There is pain in the chest area.

4. There may be a runny nose and a strong tickle in the throat.

5. There is pain in the muscles.

6. Very severe headache, shortness of breath, the person is shivering.

7. A person experiences vomiting, nausea and diarrhea, which indicates a general intoxication in the body.

After 3 days, the cough is moistened, sputum with blood may come out.

All signs of the disease develop depending on the period of the disease. For the first days of illness, it is difficult, while the body aches, toxicosis occurs, severe headache, muscle pain, chills, eyes turn red. There may be pain in the chest, shortness of breath, in which the face and fingertips turn blue, the cough is dry at first, then it can be wet, sputum is shed with blood. Moist rales are heard in the lungs.

Causes of viral pneumonia

Due to the fact that viruses enter the lungs, this disease develops, it can be infected by airborne droplets when a person inhales it. Most often, the causative agent of viral pneumonia in children is adenovirus, respiratory syncytial, influenza virus or parainfluenza. The measles virus can also cause pneumonia, especially in children who are very weak. In adults, pneumonia is caused by two influenza viruses, A and B, the varicella-zoster virus. Those who have problems with the immune system, due to the fact that cytomegalovirus or herpes virus enters, develop a severe form of pneumonia.

Diagnosis of viral pneumonia

Most often, the diagnosis is made on the basis of an examination that indicates respiratory failure and weakening in the respiratory system. An x-ray is required. It can detect blackout and diffuse infiltration.

A general blood test shows a moderate increase in leukocytes, and vice versa, a decrease can be. Always in this situation increased ESR.
The diagnosis is confirmed on the basis of taking mucus in the throat, nasopharynx, nose, also when the titers of antibodies in the blood to certain types of viruses increase.

To make a diagnosis of viral pneumonia, you need to pay attention to the following factors:

1. Take into account the epidemiological situation regarding influenza and other acute respiratory diseases.

2. Pay attention to flu symptoms and other acute respiratory infections.

3. X-ray shows changes in the lungs.

4. The virus is found in the mucus of the nose, throat and nasopharynx.

5. Antibody titers in the blood rise up to 4 times.

Treatment of viral pneumonia

It is carried out in stationary conditions, for this antibiotics are used, as well as oxygen inhalation, detoxification therapy. In viral pneumonia, antiviral drugs are not prescribed, only in severe and serious cases. If pneumonia is due to the herpes virus or chickenpox, acyclovir is prescribed. Viral pneumonia can be a complication of influenza, so it is best to get vaccinated annually as a preventive measure.

Influenza-like viral pneumonia

The disease begins acutely, while the body temperature can rapidly rise, chills occur, there may be intoxication, with a severe headache, aching bones, muscle pain, no appetite, vomiting and nausea. A paroxysmal cough may be present, followed by a mucous sputum with blood. Bronchospasm often occurs.

X-ray of the lungs shows the lesion and enhanced vascular pattern. When viral-bacterial pneumonia develops, the lungs can be affected.

A special form of pneumonia is hemorrhagic. It is severe and the symptoms of intoxication are pronounced. In this case, the cough is immediately with bloody sputum, then its amount increases sharply. At the same time, body temperature rises, cyanosis, shortness of breath occurs. In the following days, respiratory failure may develop, the lungs swell, all this ends in a hypoxic coma and death.

Pneumonia is caused by different viruses

1. Parainfluenza.

2. Adenoviruses.

3. Respiratory syncytial virus.

The symptoms are similar to influenza pneumonia, but this form of pneumonia has much less fever and may be tracheitis, a slow inflammation in the lungs.

With adenovirus pneumonia, catarrhal tracheobronchitis, prolonged cough, hemoptysis, rhinopharyngitis, persistent fever occur, lymph nodes in the neck increase, and conjunctivitis may also occur. With adenovirus pneumonia has a viral-bacterial character.

If pneumonia is caused by a respiratory syncytial virus, body temperature may rise up to 10 days, pain in the chest area occurs, wet and dry rales may occur in areas of the lungs, viral pneumonia has symptoms of rhinopharyngitis.

How is viral pneumonia different from normal pneumonia?

There is no purulent sputum, fever and intoxication. The disease can affect the alveoli, through which gas exchange occurs, because of this, disturbances in blood saturation occur, the tissues lack oxygen.

So, viral pneumonia is a serious disease that needs to be treated immediately because it can be quite dangerous. In order to protect yourself from it, you must not forget about preventive measures, be sure to monitor your lifestyle, eat rationally, and walk in the fresh air as much as possible. In case of an epidemic, avoid public places.

State sanitary and epidemiological regulation
Russian Federation

MICROBIOLOGICAL FACTORS

Laboratory diagnostics
community-acquired pneumonia

Guidelines
MUK 4.2.3115-13

Official edition

4.2. CONTROL METHODS. BIOLOGICAL AND
MICROBIOLOGICAL FACTORS

Laboratory diagnosis of community-acquired pneumonia

1 area of ​​use

1.1. These guidelines substantiate and define the methodological foundations and algorithms for the laboratory diagnosis of pneumonia in the implementation of epidemiological surveillance in relation to community-acquired pneumonia.

1.2. The guidelines are intended for specialists of bodies and institutions of the Federal Service for Supervision of Consumer Rights Protection and Human Welfare, and can also be used by specialists from medical organizations and other interested organizations.

1.3. Methodological guidelines are mandatory in the implementation of epidemiological surveillance in relation to community-acquired pneumonia, in the course of anti-epidemic measures and in the epidemiological investigation of possible epidemic outbreaks of community-acquired pneumonia.

2. Terms and abbreviations

WHO - World Health Organization.

CAP - community-acquired pneumonia.

LPO is a medical and preventive organization.

ICD-10 - international classification of diseases.

SARS is an acute respiratory viral infection.

PCR - polymerase chain reaction.

PCR-RT - polymerase chain reaction in real time.

RIF - immunofluorescence reaction.

ELISA - enzyme immunoassay.

ICA - immunochromatographic analysis.

ABT - antibacterial therapy.

ICU - resuscitation and intensive care unit.

BAL - bronchoalveolar lavage.

3. General information about community-acquired pneumonia

Pneumonia is a group of acute infectious diseases of different etiology, pathogenesis, morphological characteristics, characterized by focal lesions of the respiratory sections of the lungs with the obligatory presence of intraalveolar exudation. In the International Classification of Diseases, Injuries and Causes of Death of the 10th revision (ICD-10, 1992), pneumonia is clearly separated from other focal inflammatory diseases of the lungs of non-infectious origin. The modern classification of pneumonia takes into account, first of all, the epidemiological conditions for the development of the disease, the features of infection of the lung tissue and the state of the immunological reactivity of the patient's body. According to the nature of the acquisition, community-acquired pneumonia (CAP) and nosocomial (nosocomial) pneumonia are distinguished. Recently, in addition to the term "nosocomial pneumonia", a broader term has been used - "pneumonia associated with the provision of medical care" ( healthcare-associated pneumonia). In addition to nosocomial pneumonia, this category includes pneumonia in people in nursing homes or other long-term care facilities. It should be emphasized that such a division is in no way connected with the severity of the course of the disease, the main criterion for distinguishing is the epidemiological conditions and the environment in which pneumonia developed. However, they usually differ from CAP in terms of the etiological structure of pathogens and the profile of antibiotic resistance.

CAP should be understood as an acute disease that occurred in a community setting - that is, outside the hospital or later than 4 weeks after discharge from it, or diagnosed in the first 48 hours from the moment of hospitalization, or developed in a patient who was not in nursing homes / long-term care units observation of 14 or more days, - accompanied by symptoms of infection of the lower respiratory tract (fever, cough, sputum, possibly purulent, chest pain, shortness of breath) and radiological signs of "fresh" focal-infiltrative changes in the lungs in the absence of an obvious diagnostic alternative.

The modern classification of CAP, taking into account the state of the immunological reactivity of the patient's body, allows us to distinguish 2 main groups, suggesting differences in the etiological structure of pneumonia:

Typical CAP (in patients with no severe immune disorders);

CAP in patients with severe immune disorders (acquired immunodeficiency syndrome; other diseases or pathological conditions).

4. Modern ideas about the etiological structure of community-acquired pneumonia

The absolute significance of the etiological role of one or another causative agent of CAP can only be determined in relation to a specific region, epidemic focus, or epidemiological situation. Broader generalizations make it possible to identify the main trend that determines the significance of this pathogen in human infectious pathology based on the appropriate level of standardization and frequency of laboratory diagnostic methods, as well as the approximate ratio of EPs caused by the main causative agent of pneumonia - pneumococcus and other pathogens.

According to domestic and foreign researchers S. pneumoniae is the dominant etiological agent of pneumonia, causing from 30 to 80% of EP in people of all age groups (Pokrovsky V.I. et al., 1995; Zubkov M.N., 2002, Cuhna V.A., 2003, Chuchalin A.G. ., 2006).

Against the background of an increase in contingents with severe immunity defects (HIV infection, congenital immunodeficiency, oncohematological diseases, etc.), in recent years, the etiological significance of such opportunistic CAP pathogens as Pneumocystis juroveci, cytomegalovirus. Taking into account the high level of carriage of these pathogens, the diagnosis of the corresponding nosology should be carried out only in risk groups using modern laboratory research algorithms.

The concept of "viral pneumonia" has not yet been widely used in the diagnosis of CAP, however, ICD-10 distinguishes pneumonia caused by influenza viruses, parainfluenza, adenoviruses and others from the group of respiratory tract infection pathogens. At the same time, the viral and bacterial etiology of CAP is widely known and described against the backdrop of epidemics of influenza and acute respiratory infections. The national standard for specialized medical care for severe pneumonia with complications includes J10.0 "Influenza with pneumonia" (influenza virus identified) and J11.0 "Influenza with pneumonia" (influenza virus not identified) as nosological units.

Viral respiratory tract infections are more severe in children under 5 years of age and the elderly (over 65 years of age), which is reflected in the high rate of hospitalizations for pneumonia and mortality among people of this age. In these age groups, viral and viral-bacterial pneumonias are more often recorded.

During influenza epidemics, the risk of developing pneumonia may increase for those age groups in which the level of anamnestic antibodies to the antigenic variant of the influenza virus circulating in a particular epidemic season is lower than protective, as, for example, was observed in the case of pandemic influenza A / H1N1pdm2009 for persons from 30 to 60 years. People suffering from chronic diseases of the cardiovascular system, metabolic disorders (obesity, diabetes mellitus), chronic diseases of the bronchopulmonary system, and pregnant women should also be included in the risk groups for developing pneumonia with influenza.

The etiological structure of CAP in children differs significantly from the etiology of CAP in adults and varies depending on the age of the child and the severity of the disease, which should be taken into account in the algorithm for diagnosing pneumonia in children. Risk groups for severe pneumonia are children under 5 years of age, frequently ill children, and especially those born at 24-28 weeks of gestation.

Bacterial causative agents of pneumonia are found in 2 - 50% of children, more often in hospitalized children, compared with children who are on outpatient treatment. The most common bacterial pathogens of community-acquired pneumonia in children older than one year are S. pneumoniae, less often isolated H. influenzae type b, S. pneumoniae is the cause of one-third of radiologically confirmed pneumonias in children under 2 years of age. In cases of severe pneumonia requiring intensive care, an infection caused by group A streptococci or S. aureus, which are found in 3-7% of cases. Moraxella catarrhalis found from 1.5 to 3.0% of cases of pneumonia in children. Mixed viral-bacterial pneumonia is diagnosed in children according to various data in 8.2 - 33.0% of cases, and when taking into account all mixed: bacterial or viral-bacterial pneumonia in children, their frequency ranges from 8 to 40%. Among pneumococcal pneumonias in children, a combination with viral infections is noted in 62% of cases.

With CAP in children, it is necessary to take into account the possibility of a mixed bacterial-viral infection, the etiological significance of well-known and recently discovered respiratory viruses: respiratory syncytial, metapneumovirus, bocavirus and rhinoviruses. Various viral pathogens of respiratory infections are found in 30-67% of cases of pneumonia in children, and their proportion is higher in young children (up to 80% of cases from 3 months to 2 years), and are much less common in children older than 10 years. M. pneumoniae And C. pneumoniae predominantly cause pneumonia in children of school age, and are not typical for children from 1 to 5 years of age. These pathogens are more often detected during epidemic rises in the incidence in the foci of infection.

In endemic regions and according to epidemiological indicators, in the etiological diagnosis of CAP, it is necessary to take into account the possibility of zoonotic infections, which are characterized by inflammatory processes in the lungs (Q fever, psittacosis, tularemia, etc.). An important element of the examination of patients with CAP is the exclusion of the etiological role of the causative agent of tuberculosis and other mycobacteria.

5. Logistics support for laboratory research

1. Laminar box of the 2nd class of biological safety.

2. Binocular microscope with an illuminator, a set of objectives and eyepieces.

3. Electric thermostats for growing bacteria, maintaining the temperature in the chamber within (37 ± 1) °C.

4. CO 2 -incubator that maintains the temperature in the chamber within (37 ± 1) ° C, the content of CO 2 at the level of 3 - 7% or an anaerostat.

5. Distiller.

6. Electric autoclave.

7. Refrigerator maintaining a temperature of 4 - 6 °C for storage of cultures, biological substrates and reagents.

8. Spirit lamps and gas burners.

9. Colony counters automatic and semi-automatic for counting colonies.

10. Disposable sterile containers for collecting and transporting sputum, pleural fluid, tracheal aspirate, BAL with a stable base, made of transparent material (preferably plastic to prevent breakage, facilitate disinfection and disposal of the container); the lid should hermetically close the containers and be easy to open; the container should not contain chemicals that adversely affect the viability of the bacteria present in the sputum.

11. A set of reagents for Gram staining of micropreparations.

12. Culture media S. pneumoniae(e.g. blood agar, CNA agar).

13. Nutrient media for the cultivation of bacteria of the genus Haemophilus(e.g. chocolate agar), Gram-negative bacteria and S. aureus(Endo agar, MacConkey, yolk-salt agar).

14. Bacteriological dishes (Petri) for growing microbiological cultures.

15. Slides and coverslips of standard sizes for micropreparations.

16. Racks and trays for test tubes and containers, transportation of Petri dishes, cuvettes and rail racks for fixing and staining smears.

17. Bacteriological loops.

18. Variable volume dispensers, semi-automatic.

19. Sterile tips for variable volume pipettes.

20. Drygalski's spatulas are sterile.

21. Measured laboratory glassware.

22. Plastic pasteur pipettes for volume standardization and transfer of liquids.

23. McFarland turbidity standard or instrument for determining the concentration of bacterial cells.

24. Discs with antibiotics (optochin, oxacillin, cefoxitin, etc.).

25. Enzyme immunoassay analyzer included.

26. Fluorescent microscope included.

27. Equipment for a PCR laboratory equipped in accordance with MU 1.3.2569-09

28. Diagnostic kits of reagents (test systems) for the detection of antigens and DNA/RNA of pneumonia pathogens, as well as specific antibodies to pneumonia pathogens, approved for use in the Russian Federation in the prescribed manner.

6. Diagnosis of community-acquired pneumonia

6.1. Diagnosis of pneumococcal pneumonia

Streptococcus pneumoniae (S. pneumoniae) is the most common bacterial causative agent of CAP. Pneumococcal pneumonias are registered in patients of any age, they occur both in outpatient practice and in a hospital (including among those hospitalized in the ICU). An increase in the incidence of CAP pneumococcal etiology in the Northern Hemisphere is observed in the winter season; pneumococcal pneumonia is more often recorded among patients with concomitant chronic diseases - chronic obstructive pulmonary disease, diabetes mellitus, alcoholism, asplenia, immunodeficiency, often occurs with bacteremia (up to 25 - 30%).

Pneumococcal CAP usually has an acute onset, high fever, and chest pain. However, clinical, laboratory and radiological manifestations of CAP caused by S. pneumoniae, are not sufficiently specific and cannot be considered an adequate predictor of the etiology of the disease.

For the diagnosis of pneumococcal CAP, culture methods are most often used. The clinical material for the study is sputum, venous blood, less often - invasive respiratory samples (BAL, material obtained during bronchoscopy, protected brush biopsy, etc.) and pleural fluid.

When examining sputum, special attention should be paid to the need to assess the quality of the delivered sample. The analysis must begin with the preparation of a smear, since the results of microscopy affect not only the assessment of the suitability of the material, but also the further direction of bacteriological research. The criteria for the suitability of sputum for bacteriological examination is the presence of more than 25 segmented leukocytes and no more than 10 epithelial cells per field of view when viewing at least 20 fields of view of a Gram-stained smear (at × 100 magnification). Microscopy of a Gram-stained smear (under a magnification of × 1,000 using an immersion lens) reveals Gram-positive cocci (usually lanceolate diplococci) 0.5–1.25 µm in diameter, without spores and flagella; most have a polysaccharide capsule.

The study of the pleural fluid involves bacterioscopy of a Gram-stained smear followed by a cultural study. It is performed in the presence of pleural effusion and conditions for safe puncture (visualization on the laterogram of a freely displaceable fluid with a layer thickness > 1.0 cm). Culture of invasive respiratory samples in CAP is recommended for immunocompromised patients, this method can be used in some cases with severe CAP, as well as ineffective initial antibiotic therapy (ABT).

Clinically significant in an acute inflammatory process are microorganisms isolated from BAL in an amount of ≥ 10 4 CFU / ml, from biopsy obtained using protected brushes - ≥ 10 3 CFU / ml, sputum - ≥ 10 5 CFU / ml.

To highlight S. pneumoniae from clinical material, it is necessary to use nutrient media enriched with defibrinated blood of animals (ram, horse or goat) at a concentration of 5%. Somewhat worse results are obtained by the use of defibrinated human blood. Due to the scarcity of defibrinated blood in practical laboratories and its short shelf life, it should be remembered that commercially prepared chocolate agar can be used to isolate pneumococci, which is also used in parallel to isolate hemophilia. Another cultivation condition S. pneumoniae- incubation in an atmosphere with a content of CO 2 increased up to 3 - 7%, since it is a facultative anaerobe. Probability of selection S. pneumoniae from respiratory samples increases when using selective media containing additives that inhibit the growth of saprophytic and gram-negative microorganisms (colistin, nalidixic acid, gentamicin).

The key test for differentiating pneumococci from other α-hemolytic streptococci is optochin sensitivity (the test is based on the ability of optochin to selectively suppress the growth of pneumococcus in contrast to other viridescent streptococci). However, among S. pneumoniae the number of optochin-resistant strains is growing, which requires the use of alternative methods for identifying the pathogen (lysis in the presence of bile salts, the Neufeld test, agglutination with diagnostic pneumococcal sera).

The informativeness of the cultural study of respiratory samples and blood largely depends on compliance with the generally accepted rules for their collection, storage and transportation (see appendix). In addition, the likelihood of finding St. pneumoniae decreases significantly when receiving clinical samples against the background of systemic ABT. For blood culture, it is preferable to use commercial culture vials.

Among the non-cultural methods for diagnosing pneumococcal pneumonia, the most widely used in recent years has been an immunochromatographic test, which involves the detection of pneumococcal cell polysaccharide antigen in the urine. Its main advantage is the ability to use "at the bedside" due to the ease of implementation and quick results. The pneumococcal rapid test demonstrates acceptable sensitivity (50-80%) and fairly high specificity (> 90%) for CAP in adults compared to traditional methods. Disadvantages of the test include the possibility of false-positive results in pneumococcal carriers (the test is not recommended for children under 6 years of age) and in individuals with recent CAP.

Methods for identifying St. pneumoniae in clinical material using PCR. As targets for amplification, autolysin genes ( lytA), pneumococcal surface antigen ( psaA) and pneumolysin ( ply) and other target genes. However, these methods are not widely used in clinical practice, and their place in the etiological diagnosis of CAP needs to be clarified.

6.2. Diagnosis of other bacterial pneumonias

An important clinically significant bacterial causative agent of CAP is haemophilus influenzae (H. influenzae). Community-acquired pneumonia is usually caused by non-typable strains H. influenzae. According to a number of studies, H. influenzae more common in patients with concomitant COPD and active smokers, the incidence of infection with this pathogen is higher in patients with non-severe CAP.

Family representatives Enterobacteriaceae (Klebsiella pneumoniae, Escherichia coli etc.) and Pseudomonas aeruginosa (P. aeruginosa) are detected in less than 5% of patients with CAP and are classified as rare pathogens. However, the significance of these microorganisms may increase in patients with severe CAP, and infection several times increases the likelihood of a poor prognosis.

As epidemiological studies show, the incidence of enterobacteria is higher in patients with chronic concomitant diseases, in persons who abuse alcohol, with aspiration, in case of recent hospitalization and previous antibiotic therapy. Additional risk factors for infection P. aeruginosa are chronic bronchopulmonary diseases (severe COPD, bronchiectasis), long-term use of systemic steroids, cytostatics.

Another bacterial pathogen Staphylococcus aureus (S. aureus) - is rare among outpatients with CAP, at the same time, in people with a severe course of the disease, its share can increase to 10% or more. to infection S. aureus Predispose many factors - old age, living in nursing homes, drug addiction, alcohol abuse. It is known that the relevance S. aureus as a causative agent of VP increases significantly during influenza epidemics.

There are no specific clinical, laboratory, or radiological signs typical of CAP caused by these pathogens and distinguishing it from pneumonia of another etiology. In some cases, mainly in people with immunosuppression or alcohol abuse, K. pneumoniae can cause lobar pneumonia with localization of the lesion in the upper lobe of the lung, rapid progression of symptoms of the disease and high mortality.

For the etiological diagnosis of CAP caused by these pathogens, the cultural method of research is of primary importance. H. influenzae, like pneumococcus, belongs to the category of "capricious" microorganisms, requiring for cultivation the presence of factors X, V and 5-7% CO 2 in the nutrient media in the incubation atmosphere. To highlight H. influenzae from clinical material, chocolate agar or selective agar is usually used to isolate bacteria of the genus Haemophilus. Sowing of clinical material in order to identify members of the family Enterobacteriaceae And P. aeruginosa carried out on selective media for the isolation of gram-negative bacteria (Endo agar, McConkey, etc.), S. aureus- on yolk-salt agar, mannitol-salt agar, etc.

Clinical specimens may include sputum, venous blood, invasive respiratory specimens, and pleural fluid. In the study of sputum, as well as for the detection of pneumococci, it is important to evaluate the quality of the collected sample. The study of pleural fluid is performed in the presence of pleural effusion and conditions for safe pleural puncture, invasive respiratory samples - only for certain indications.

It should be noted that non-typable strains H. influenzae And S. aureus are part of the normal microflora of the upper respiratory tract (URT), and the frequency of asymptomatic carriage can be quite high. With age, in the presence of chronic comorbidities, as well as recent systemic antibiotic therapy, the frequency of colonization of the oral cavity and upper respiratory tract by enterobacteria increases. This fact must be taken into account in the clinical interpretation of the results of bacteriological examination of respiratory samples, especially sputum.

The informativeness of the cultural study of respiratory samples and blood largely depends on compliance with the generally accepted rules for their collection, storage and transportation. Identification is based on the determination of the nutritional requirements of pathogens and the results of biochemical tests. To identify all these microorganisms, commercial biochemical panels and reagent kits have been developed; automated microbiological analyzers can be used, which reduce the laboriousness of cultural studies.

If you suspect a EP caused by S. aureus, it is important not only to isolate and identify the pathogen, but also to determine its sensitivity to oxacillin. Despite the lack of documented evidence of the detection of methicillin-resistant S. aureus in patients with CAP in the Russian Federation, the risk of their occurrence and spread is quite real. Among the phenotypic methods for detecting methicillin resistance, the most commonly used testing is by the disk diffusion method with a disk containing 30 µg of cefoxitin or 1 mg of oxacillin, or screening on Mueller-Hinton agar with the addition of 4% NaCl and oxacillin at a concentration of 6 mg/l. To confirm infection with methicillin-resistant S. aureus commercial test systems have been developed based on the detection of the gene in clinical material mecA PCR method.

6.3. Diagnosis of pneumonia caused by Mycoplasma pneumoniae

The causative agent of respiratory mycoplasmosis is Mycoplasma pneumoniae- class representative Mollicutes, which unites wallless bacteria capable of autonomous existence, occupying an intermediate position between bacteria and viruses in terms of the level of structural organization.

Respiratory mycoplasmosis is a common anthropogenic disease. A feature of respiratory mycoplasmosis is the frequency of epidemics at intervals, according to various sources, varying from 3 to 7 years. The spread of infection is facilitated by the frequency and duration of contacts among persons staying in closed and semi-closed groups (military personnel, boarding schools), especially during their formation.

In 3-10% of cases of mycoplasmal infection, pneumonia is diagnosed radiographically. With pneumonia caused M. pneumoniae, other bacterial or viral pathogens are usually not detected, but in rare cases it is also isolated S. pneumoniae. In 1-5% of cases of respiratory mycoplasmosis, hospitalization is required.

Mycoplasma pneumonia is accompanied by frequent painful and prolonged cough with scanty viscous sputum, which is poorly evacuated, chest pains are noted, bronchial obstruction may develop. Intoxication is unsharply expressed. Physical changes in the lungs are absent or mild. The radiological picture is very variable. In most cases, interstitium lesions are detected, in some patients pneumonia proceeds as focal or segmental, sometimes inflammatory changes are mixed. The phenomena of pulmonary insufficiency are uncharacteristic of mycoplasmal pneumonia. Mycoplasma pneumonia usually has a favorable course, in rare cases the course is very severe.

Diagnosis of mycoplasmal pneumonia only on the basis of clinical or radiological data is impossible, since it does not have pathognomonic features. The main role in confirming the mycoplasmal etiology of pneumonia is given to laboratory etiological diagnosis. For the etiological diagnosis of mycoplasmal pneumonia, the following are used:

DNA detection M. pneumoniae polymerase chain reaction (PCR), the main method for direct detection of DNA M. pneumoniae is currently the standard polymerase chain reaction (PCR) with detection by electrophoretic DNA separation, however, PCR with real-time detection (RT-PCR) has the highest specificity and sensitivity;

Detection of mycoplasma antigen in the direct immunofluorescence reaction (RIF);

Serological studies for the detection of specific antibodies of the IgM and IgG class to M. pneumoniae in blood sera by enzyme immunoassay (ELISA).

Mycoplasma pneumoniae refers to difficult-to-cultivate microorganisms; the isolation process takes 3 to 5 weeks, so the culture method cannot be recommended for use by diagnostic laboratories.

For the purpose of rapid etiological diagnosis of pneumonia, it is recommended to use PCR in the study of biological material obtained from the lower respiratory tract (sputum with deep cough, aspirates from the trachea, sputum obtained as a result of induction by inhalation of hypertonic sodium chloride solution, bronchoalveolar lavage fluid (BAL) obtained using fiberoptic bronchoscopy).

Upon receipt of a positive PCR result in the study of biological material obtained from the lower respiratory tract, the etiology of pneumonia is considered established. If it is not possible to obtain biological material from the lower respiratory tract for PCR, it is acceptable to use smears from the upper respiratory tract (combined swab from the nasopharynx and posterior pharyngeal wall), and if a positive result is obtained, the etiology of pneumonia should be considered presumably established. However, obtaining a negative PCR result in the study of smears from the upper respiratory tract cannot indicate the absence of mycoplasma infection. In this case, serological diagnostics is recommended, taking into account the totality of results for the detection of specific antibodies of the IgM and IgG classes in paired sera tested simultaneously.

For the purpose of retrospective diagnosis, when the patient is already in the stage of convalescence, it is necessary to use serological studies.

The primary immune response is characterized by the synthesis of IgM antibodies 1–3 weeks after infection, the detection of which indicates the acute phase of infection. Class G immunoglobulins appear by the end of 3-4 weeks. The diagnosis of mycoplasmal respiratory infection is confirmed by 4-fold seroconversion of specific antibodies in paired blood sera.

Direct detection of antigens M. pneumoniae in various biosubstrates (smears from the nasopharynx, lavage fluid, biopsy specimens) obtained from patients with respiratory pathology, until now, in separate diagnostic laboratories, they are carried out using RIF. This method, combined with the detection of specific antibodies to mycoplasma in ELISA, makes it possible to confirm the disease caused by Mycoplasma pneumoniae. It should be borne in mind that humoral antibodies persist for several years.

For reliable and final etiological diagnosis of mycoplasmal pneumonia, taking into account the possibility of persistence of this pathogen in the human body without pronounced clinical manifestations, additional confirmation of the established diagnosis by any of the methods listed above is recommended.

6.4. Diagnosis of pneumonia caused by Chlamydophila pneumoniae

C. pneumoniae causes pneumonia of varying severity, long-term bronchitis, pharyngitis, sinusitis. pneumonia caused by C. pneumoniae usually has a favorable course, in rare cases the course is very severe.

Mixed infection, such as a combination with pneumococcus or the presence of severe comorbidities, especially in the elderly, complicates the course of the disease and increases the risk of death. Often, the infection is asymptomatic.

All ages are at risk, but the incidence of chlamydial pneumonia is higher in school-age children. The incidence among men is higher than among women. Epidemic outbreaks occur every 4 to 10 years. Epidemiological outbreaks in isolated and semi-isolated groups, cases of intrafamilial transmission of chlamydial infection are described.

None of the currently known methods for diagnosing chlamydial pneumonia provides 100% reliability of pathogen detection, which dictates the need for a combination of at least two methods.

Microbiological isolation C. pneumoniae is of limited use due to the fact that it is a long and laborious process, characterized by low sensitivity and is available only to specialized laboratories. However, if a viable pathogen is isolated, the diagnosis can be made with the greatest certainty without the need for confirmatory tests. Cultural isolation indicates an active infectious process, since with persistent infection, the pathogen passes into an uncultivated state.

The most specific and sensitive method for detecting the pathogen is PCR diagnostics. High sensitivity and absence of false-positive results can be ensured by using only licensed kits for efficient DNA extraction from clinical material and modern-generation PCR kits based on real-time PCR (RT-PCR). The method does not make it possible to differentiate acute and chronic infection.

For the purpose of rapid etiological diagnosis of pneumonia, it is recommended to use PCR in the study of biological material obtained from the lower respiratory tract (sputum with deep cough, aspirates from the trachea, sputum obtained as a result of induction by inhalation of hypertonic sodium chloride solution, bronchoalveolar lavage fluid (BAL) obtained using fiberoptic bronchoscopy). Serological tests are used for retrospective diagnosis and retrospective analysis of the nature of epidemic outbreaks.

Upon receipt of a positive PCR result in the study of biological material obtained from the lower respiratory tract, the etiology of pneumonia is considered established. However, in pneumonia caused by Chlamydophila (Chlamydia) pneumoniae, cough is often non-productive, in such cases, PCR is recommended to use swabs from the upper respiratory tract (combined smear from the nasopharynx and posterior wall of the pharynx), and if a positive result is obtained, the etiology of pneumonia should be considered presumably established.

Upon receipt of a negative PCR result in the study of swabs from the upper respiratory tract in case of suspected infection caused by C. pneumoniae, based on epidemiological or clinical data, serological diagnosis is recommended, taking into account the totality of results for the detection of specific antibodies of the IgM and IgG classes in paired sera tested simultaneously.

For the purpose of retrospective diagnosis, when the patient is in the stage of convalescence, it is necessary to use serological studies.

Currently, to detect specific IgM and IgG antibodies to C. pneumoniae use the method of enzyme immunoassay (ELISA) or immunofluorescence reaction (RIF). Serological criteria for acute C. pneumoniae- infections: a 4-fold increase in IgG antibody titers in paired sera or a single detection of IgM antibodies in a titer ≥ 1:16.

For a reliable and final etiological diagnosis of chlamydial pneumonia, taking into account the possibility of persistence of this pathogen in the human body without pronounced clinical manifestations, additional confirmation of the established diagnosis by any of the methods listed above is recommended.

6.5. Diagnosis of pneumonia caused by Legionella pneumonia

Due to the similarity of clinical manifestations and symptoms of legionella and pneumococcal pneumonia, rapid and effective laboratory diagnostics is of decisive importance for the choice of tactics for etiotropic therapy of patients. In 1999, the WHO and in 2002 the European Working Group on Legionellosis adopted standards as diagnostic criteria, according to which the diagnosis of legionellosis in the case of an acute infection of the lower respiratory tract (clinically and radiographically confirmed) is considered established:

1) when isolating a culture of legionella from a separated respiratory tract or lung tissue;

2) with a 4-fold or more increase in the titer of specific antibodies to Legionella pneumophila serogroup 1 in the indirect immunofluorescence reaction;

3) when determining a soluble antigen Legionella pneumophila serogroup 1 in the urine by enzyme immunoassay (ELISA) or immunochromatographic method (IHA).

In the absence of blood serum taken in the early stages of the disease, the detection of a significantly high level of antibodies to Legionella pneumophila serogroup 1 (1:128 and above) in a single serum by indirect immunofluorescence allows us to consider the diagnosis of legionellosis presumably established. Similarly, the results obtained on the basis of the detection of the pathogen or its DNA in the respiratory secretion or lung tissue using direct immunofluorescence or PCR are interpreted.

Paragraphs 2 and 3 of the laboratory diagnostic standards currently apply only to antibodies and antigen determined for Legionella pneumophila serogroup 1. For other serogroups Legionella pneumophila the results obtained by the determination of antibodies or the detection of antigen in the urine, allow only a presumptive diagnosis. Isolation of the culture of the pathogen remains the only method of standards that establishes the final diagnosis in the case of infection caused by other serogroups Legionella pneumophila or types Legionella spp.. At the same time, it should be noted that more than 80% of sporadic and group cases of legionellosis are caused by strains Legionella pneumophila serogroup 1, and in epidemic outbreaks of community-acquired pneumonia, the etiological significance of strains L. pneumophila serogroup 1 was confirmed in 96% of cases.

The main standard method that currently allows timely diagnosis and monitoring of legionella infection is the determination of legionella antigen in urine by immunochromatographic or enzyme immunoassay. The method allows you to finally confirm the diagnosis within 1-2 hours. The superiority of this method over other methods included in the standard lies primarily in the timing of the study and the availability of clinical material.

The bacteriological method takes at least 4-5 days, and invasive procedures are required to obtain bronchoscopy and biopsy material, since it is not always possible to isolate the pathogen from sputum, especially after the start of etiotropic therapy. Identification of a diagnostic increase in antibody titers in the reaction of indirect immunofluorescence is possible only at the 3rd week of the disease, when a course of antibiotic therapy is performed and the outcome of the disease is usually clear. The need to study paired sera determines the retrospective nature of the diagnosis of legionellosis by this method.

The PCR method can be recommended primarily for the study of BAL or biopsy for suspected legionella pneumonia in immunocompromised patients. If in this category of patients the infection is caused by strains L. pneumophila that do not belong to serogroup 1, then this method is the only one that allows you to quickly establish a diagnosis.

6.6. Diagnosis of pneumonia caused by Pneumocystis jiroveci

Pneumocystosis, as a rule, occurs in the form of acute respiratory diseases, exacerbations of chronic bronchopulmonary diseases, obstructive bronchitis, laryngitis, and also as pneumonia with gas exchange disorders (interstitial pneumonia).

A typical radiographic picture in pneumocystis pneumonia is represented by bilateral hilar interstitial infiltration of the lung tissue with increasing intensity and a large amount of damage in direct proportion to the progression of the disease. Less common are single and multiple lung tissue seals, upper lobe infiltrates and pneumothorax. Pleurisy and enlarged intrathoracic lymph nodes are rare. In the absence of pathology on radiographs, high-resolution CT may detect ground glass changes or cellular deformity of the lung pattern.

In adults, pneumocystis pneumonia usually develops against the background of secondary immunodeficiency. The incubation period is short - from 2 to 5 days, the onset is acute. Pneumocystis pneumonia can develop in patients receiving immunosuppressive therapy (corticosteroids). With medical immunosuppression, this disease manifests itself against the background of a decrease in the dose of corticosteroids. The prodromal period usually lasts 1 to 2 weeks; in AIDS patients - 10 days.

Pneumocystis pneumonia in AIDS is usually characterized by a sluggish chronic process. Initially, auscultatory symptoms are not detected. Respiratory failure associated with a sharp violation of lung ventilation and gas exchange leads to a fatal outcome. Abscesses, spontaneous pneumothorax and exudative pleurisy are also possible.

Pneumocystosis in children usually develops on the 4th - 6th month of life, when the immune system of the newborn has not yet fully formed. The most susceptible to this disease are premature, sick with rickets, with malnutrition and lesions of the central nervous system.

In young children, pneumocystosis proceeds as a classic interstitial pneumonia with clear stages of pathological processes.

Based on morphological changes in the overt course of the disease, three stages of the affected lung are distinguished:

Edema (7 - 10 days);

Atelectatic (up to 4 weeks);

Emphysematous (its duration is variable).

risk groups for infection Pneumocystis jiroveci are:

Premature children, debilitated newborns and young children with hypogammaglobulinemia, malnutrition and rickets;

Patients with leukemia, cancer patients, recipients of organs receiving immunosuppressants;

Patients with tuberculosis, cytomegaly and other infections;

HIV-infected.

The most universal for the detection of cysts, trophozoites and sporozoites is the Romanovsky-Giemsa method. Vital staining with neutral red also allows you to identify the pathogen in the active phase.

All of the above staining methods require highly qualified researcher for accurate identification. Pneumocystis jiroveci; in addition, these methods serve only for indication and are aimed at common fungal polysaccharides of the cyst envelope.

Immunofluorescent method (IF) for the detection of cysts and trophozoites using monoclonal or polyclonal antibodies in lavage fluid has higher specificity and sensitivity than histochemical staining of preparations.

An immunological method that detects specific antibodies of the IgG and IgM classes (ELISA) also plays a significant role in the diagnosis of pneumocystosis, especially in the diagnosis when it is impossible to take lavage fluid or sputum from a patient. Antibodies of class G among the healthy population are detected quite often (60 - 80%). Therefore, the study of antibodies should take place in dynamics with mandatory titration of serum. Detection of a 4-fold increase in IgG and / or detection of IgM antibodies against Pneumocystis jiroveci speaks of an acute infectious process caused by this pathogen.

Polymerase chain reaction (PCR) is one of the highly sensitive diagnostic methods that allows you to detect single cells or DNA fragments of the pathogen Pneumocystis jiroveci in sputum or bronchoalveolar lavage.

6.7. Diagnosis of viral and viral-bacterial pneumonia

Viral or viral-bacterial etiology of pneumonia in adults can be suspected during the rise in the incidence of influenza and SARS, as well as when group cases of the disease occur within a month after the formation of closed and semi-closed teams. The risk group for a severe course of viral pneumonia includes people suffering from heart failure and chronic diseases of the bronchopulmonary system. Concomitant pathology in severe influenza are also obesity, diabetes, pregnancy, especially in the third trimester.

The main causative agents of viral and viral-bacterial pneumonia in immunocompetent adults are influenza A and B viruses, adenoviruses, PC-virus, parainfluenza viruses; metapneumovirus is found less frequently. In adult patients with influenza, complications develop in 10-15% of cases, and 80% of them are pneumonia.

It is important to diagnose viral infections in children with CAP in the etiological structure of which viral infections play a significant role.

Modern methods of etiological diagnosis of acute viral infections of the respiratory tract are primarily based on: detection of RNA / DNA pathogens by nucleic acid amplification methods, in particular, using the most widely used PCR; on the detection of antigens by immunochromatography (IHA), enzyme immunoassay (ELISA), immunofluorescence (RIF). The methods for detecting specific antibodies in the blood serum (complement fixation reaction (RCC), neutralization reaction (PH), hemagglutination inhibition reaction (RTGA), indirect hemagglutination reaction (RIHA), enzyme immunoassay (ELISA)) remain important mainly for retrospective diagnosis. Cultivation is possible for influenza A and B viruses, respiratory syncytial virus, parainfluenza viruses types 1-3, human metapneumovirus and adenoviruses.

Cultural studies are laborious and time consuming; in routine practice, they are used only for monitoring influenza, while the initial detection of positive samples is carried out in PCR, then isolation in culture is carried out.

Immunofluorescence reactions can detect antigens of influenza viruses, respiratory syncytial virus, parainfluenza viruses 1-3 and adenoviruses. Material for research by immunofluorescence should be collected no later than three days from the onset of a respiratory infection (in the acute phase of the disease, since the method is most effective when the intracellular content of viral antigens is the highest), which makes this method uninformative for the etiological diagnosis of pneumonia. In addition, the method is subjective in interpreting the results of the analysis.

Serological tests detect antibodies to respiratory syncytial virus (PH, RSK, RNHA, ELISA), parainfluenza 1-4 viruses (RTGA, RSK, ELISA), adenoviruses (ELISA), rhinoviruses (RSK); research is usually retrospective. Compared to CSC, ELISA is more sensitive. During interpretation, the change in the titer of specific antibodies over time in paired sera (obtained with an interval of 2 weeks) is evaluated, and their results largely depend on the state of the patient's immune system.

The recognized evidence of primary viral pneumonia (or mixed viral-bacterial pneumonia) according to international criteria (ESCMID 2011, BTS, 2009 - 2011) is the detection of nucleic acids of the influenza virus or other respiratory virus by PCR. More often, swabs from the nasopharynx and from the posterior pharyngeal wall are used for diagnosis, while the greatest sensitivity due to the higher content of viruses in the test sample can be achieved with a combination of smears from both loci. For this purpose, swabs are taken from the patient with two different probes from the mucous membrane of the lower nasal passage, and then from the posterior wall of the oropharynx, while the tampons from both probes are sequentially broken off into one tube after taking the smears.

However, in the case of influenza viruses that replicate in lung tissue (A/H5N1, A/H1N1pdm2009), in the second week of pneumonia, the concentration of the virus in swabs may already be insufficient for its detection, especially with inadequate material sampling. In addition, in order to simultaneously detect both viral and bacterial agents, it is advisable to use material from the lower respiratory tract (sputum from deep coughing, sputum obtained as a result of induction by inhalation of hypertonic sodium chloride solution, aspirates from the trachea, bronchoalveolar lavage fluid (BAL) obtained by fiberoptic bronchoscopy).

To identify the most significant pathogens of acute respiratory viral infections: influenza A and B viruses, PC-virus, metapneumovirus, parainfluenza viruses 1-4, coronaviruses (229E, OS43, NL63, HKUI), rhinoviruses, adenoviruses (B, C, E), bocavirus, PCR kits are available in formats with electrophoretic detection, fluorescence endpoint detection, and real-time detection of accumulation of amplification products (RT-PCR). The maximum level of specificity and sensitivity is achieved by tests based on real-time PCR, tests with simultaneous detection of several pathogens have an advantage. The use of specific conservative regions of the viral genome as targets leads to high diagnostic sensitivity and specificity of PCR, approaching 100%, as compared with a culture study. When diagnosing influenza, it is possible to determine the subtype of influenza A viruses, including the highly pathogenic avian influenza virus A/H5N1 and the new pandemic variant A/H1N1pdm2009, the so-called swine influenza virus.

Polymerase chain reaction in the format of electrophoretic detection requires special measures to prevent contamination (false positive results), achieved by carrying out special measures and observing special rules for organizing a laboratory in accordance with MU 1.3.2569-09 “Organization of the work of laboratories using nucleic acid amplification methods when working with material containing microorganisms of I - IV groups of pathogenicity.

The etiology of “pneumonia caused by the influenza virus” should be considered established if influenza virus RNA (or in combination with other viruses) is detected by PCR in the material of the lower respiratory tract with a negative result of a bacteriological blood test (or in the absence of DNA of bacterial pathogens of pneumonia in the blood according to PCR results, or when insignificant concentrations of DNA are detected in the material of the lower respiratory tract in quantitative PCR). If it is impossible to obtain material from the lower respiratory tract, the influenza etiology of pneumonia can most likely be proved if influenza virus RNA is detected in swabs from the nasopharynx and oropharynx.

The etiology of pneumonia caused by other respiratory viruses is considered to be established if one respiratory virus (or several viruses simultaneously) is detected by PCR RNA/DNA in the material of the lower respiratory tract with a negative result of a bacteriological blood test (or in the absence of DNA of bacterial pathogens of pneumonia in the blood according to the results PCR, or when insignificant concentrations of DNA are detected in the material of the lower respiratory tract in quantitative PCR).

The viral etiology of pneumonia is considered presumably established if PCR detects one respiratory virus (or several viruses simultaneously) in swabs from the nasopharynx and oropharynx with a negative result of a bacteriological blood test (or in the absence of DNA of bacterial pathogens of pneumonia in the blood according to PCR results, or when insignificant concentrations of DNA are detected in the material of the lower respiratory tract in quantitative PCR), and also if bacteriological studies have not been performed.

The viral etiology of pneumonia is considered presumably established if antigens of one respiratory virus (or several viruses simultaneously) are detected by the RIF method with a negative result of a bacteriological blood test (or in the absence of DNA of bacterial pathogens of pneumonia in the blood according to PCR results, or if insignificant concentrations of DNA are detected in the material of the lower respiratory tract in quantitative PCR), as well as if bacteriological studies have not been conducted.

The viral-bacterial etiology of pneumonia is considered to be established in case of detection by PCR of RNA/DNA of one virus (or several viruses at the same time) in the material of the lower respiratory tract with a positive result of a bacteriological blood test (or detection of DNA of significant concentrations in the blood or in the material of the lower respiratory tract in a quantitative PCR).

The viral-bacterial etiology of pneumonia is considered to be presumably established in the case of the detection of antigens of one respiratory virus (or several viruses simultaneously) by RIF or ICA with a positive result of a bacteriological blood test (or the detection of DNA of significant concentrations in the blood or in the material of the lower respiratory tract in quantitative PCR).

The results of serological studies make it possible to judge the presence or absence of a viral infection, against which pneumonia developed.

6.8. Differential diagnosis from zoonotic diseases that cause lung damage and tuberculosis

Differential diagnosis with zoonotic diseases that cause lung damage (ornithosis, Q fever, tularemia, etc.) is carried out according to epidemiological indicators and in regions endemic for these pathogens in accordance with the sanitary rules "Ornithosis Prevention", "Q fever Prevention", "Tularemia Prevention ". Differential diagnosis with tuberculosis is also an important and necessary component of the examination of patients with severe pneumonia.

7. Algorithm for diagnosing community-acquired pneumonia

The algorithm for laboratory diagnosis of typical CAP (in patients with no severe immune disorders) is different for severe and non-severe pneumonia, for patients with severe immune disorders and children. Timely etiological diagnosis of CAP is especially important for severe pneumonia in patients hospitalized in the ICU.

In severe pneumonia, it is first necessary to conduct a bacteriological study for pneumococcus and other bacterial etiological agents, taking into account the spectrum of their sensitivity to antibiotics, and also to exclude legionella etiology using a rapid test to determine legionella antigen in the urine of patients. During the rise in the incidence of influenza and SARS, the probability of severe pneumonia of a viral or viral-bacterial nature is quite high. In this case, the algorithm for diagnosing severe pneumonia should take into account the possibility of bacterial, viral or viral-bacterial etiology. Underestimation at the stage of laboratory diagnosis of any of the above etiological variants of severe pneumonia in ICU patients can lead to death. Mortality in severe EP can be 25 - 50%.

The term "non-severe pneumonia" is used for pneumonias that are treated on an outpatient or inpatient basis, but do not require hospitalization in the ICU. In the absence of adequate timely therapy, mild pneumonia can lead to serious complications and chronic diseases of the bronchopulmonary system. Mortality in this case can range from 1 to 10%. Along with a bacteriological study for pneumococcus and other bacterial etiological agents, taking into account the spectrum of their sensitivity to antibiotics, the diagnosis of non-severe pneumonia should take into account the possibility of mycoplasmal or chlamydial etiology. During the rise in the incidence of influenza and SARS, there is a high probability of non-severe viral pneumonia, as well as mixed infection of the mentioned viruses with bacteria, chlamydia or mycoplasmas.

Requires an extended analysis of the etiological structure of CAP in patients with severe immune disorders (acquired immunodeficiency syndrome, other diseases or pathological conditions). In addition to bacteriological testing for pneumococcus, other bacterial etiological agents, given the spectrum of their sensitivity to antibiotics, and legionella, for this group of patients, there is a high probability of developing pneumonia caused by "opportunistic etiological agents", primarily Pneumocystis jiroveci, as well as cytomegalovirus, fungi, herpes virus. Differential diagnosis with tuberculosis and other mycobacterioses is also an important and necessary component of the examination of patients with CAP, who have severe immune disorders. To exclude legionella etiology of pneumonia in immunocompromised patients, bronchoalveolar lavage or biopsy is performed using a bacteriological method, or PCR for L. pneumophila serogroups 2 - 15 and Legionella spp..

With CAP in children, polyetiology is most pronounced, which must be taken into account in the process of laboratory diagnosis. Along with a bacteriological study for pneumococcus and other bacterial etiological agents, taking into account the spectrum of their sensitivity to antibiotics, the diagnosis of pneumonia in children should take into account a wide range of respiratory viruses, and not only during epidemic increases in the incidence of influenza and SARS (influenza viruses, RS virus, metapneumovirus, parainfluenza viruses, adenoviruses, coronaviruses, bocavirus, rhinoviruses), as well as the etiological role of mycoplasmas and chlamydia. With CAP in children, there is a high probability of a mixed bacterial-viral infection, including a mixed infection with chlamydia and mycoplasmas.

8. Quality control of laboratory research

An obligatory component of modern laboratory diagnostics is the quality system of laboratory tests and ensuring its functioning. The quality system includes internal control at the stages of laboratory research and external control.

Internal quality control of microbiological studies is a set of measures and procedures performed by the laboratory aimed at preventing the adverse effects of factors that arise in the process of preparing, performing and evaluating the results of an analysis that can affect the reliability of the result.

Internal quality control includes:

1. Control over compliance with the requirements for the conditions of analysis: (laboratory premises, air environment, temperature regimes of incubation and storage, disinfection and sterilization regimes, etc.).

2. Performing the procedure for maintaining reference bacterial cultures.

3. Quality control of nutrient media.

4. Quality control of test systems and reagents.

5. Quality control of distilled water.

The structure of the organization of internal quality control, the frequency and frequency of the procedures performed are established by the quality management system in force in the laboratory in accordance with GOST ISO / IEC 17025 and GOST R ISO 15189.

Documentation of the results of the control procedures carried out is carried out in accordance with the forms approved by the current quality management system. Registration and storage of control results can be carried out on electronic media.

A mandatory section of internal quality control is the periodic, but at least 1 time per year, analysis of the results of the performed control procedures, taking into account which the quality manual of the testing laboratory is adjusted.

Ensuring internal quality control of molecular genetic (PCR) studies is additionally carried out in accordance with MU 1.3.2569-09 "Organization of the work of laboratories using nucleic acid amplification methods when working with material containing microorganisms of I-IV pathogenicity groups."

External quality control is carried out in accordance with the requirements of GOST ISO / IEC 17025 and GOST R ISO 15189 in the form of participation in interlaboratory comparative tests (ICT) and / or proficiency testing programs for indicators and at intervals in accordance with the established requirements and needs of laboratories.

9. Safety requirements

Studies of biological (clinical) material are carried out in accordance with the current regulatory legal and methodological documents regarding work with microorganisms of III-IV and I-II pathogenicity groups, depending on the type of the alleged pathogen.

Application

In order to determine the etiological agent (agents) of the infection of the lower respiratory tract in case of suspected CAP, sputum is examined during deep coughing, sputum obtained by induction by inhalation of a sterile 5% sodium chloride solution through a nebulizer, sputum obtained by aspiration from the trachea using a surgical vacuum or electric suction, bronchoalveolar lavage (BAL) obtained by fibrobronchoscopy, and blood and pleural fluid.

If it is impossible to obtain material from the lower respiratory tract during the study of respiratory viruses, mycoplasma and chlamydia, it is permissible to use smears from the upper respiratory tract (from the lower nasal passage and from the posterior pharyngeal wall), which are taken from the patient as early as possible from the onset of symptoms of acute respiratory infections in one tube and tested as one sample.

In hospitalized patients, material for research should be collected as early as possible upon admission (no later than the second day), since at a later date the possibility of superinfection through contact with other patients is not excluded. The collection of biological material for bacteriological examination should be carried out before the appointment of antibiotics.

In case of death, post-mortem (autopsy) material is examined.

Rules for obtaining freely separated sputum for bacteriological and PCR studies

Sterile, hermetically sealed plastic containers should be used to collect sputum. Before collecting sputum, ask the patient to rinse their mouth thoroughly with boiled water. Sputum collection is carried out on an empty stomach or not earlier than 2 hours after a meal.

The patient is asked to take several deep breaths, holding the breath for a few seconds, then exhale with force, which contributes to the appearance of a productive cough and the clearance of sputum from the upper respiratory tract. The patient is then asked to cough well and collect the discharge from the lower respiratory tract (not saliva!) into a sterile container. The volume of the sputum sample should be at least 3 ml for adults and about 1 ml for children.

Should be stored in a refrigerator at 4-8°C. The duration of storage of sputum at room temperature should not exceed 2 hours.

For PCR studies it is allowed to store a sputum sample for 1 day at a temperature of 2 to 8 ° C, for a longer time - at a temperature not higher than - 16 ° C.

Rules for obtaining venous blood for bacteriological examination

To collect blood for the purpose of bacteriological examination, commercial hermetically sealed glass vials or vials made of impact-resistant autoclavable plastic of two types (containing a nutrient medium for isolating aerobes and anaerobes) are used. Blood is taken with a syringe, the blood is aseptically transferred into a vial with a transport medium directly through a rubber stopper.

Two venous blood samples are taken at 20 to 30 minute intervals from various peripheral veins, such as the left and right cubital veins. One sample will be placed in the vial for aerobic isolation, the other for anaerobic isolation. The volume of blood at each venipuncture should be at least 10 ml for adults and 3 ml for children.

Immediately before venipuncture, the skin at the venipuncture site is disinfected by circular movements from the center to the periphery twice with 70% alcohol solution or 1-2% iodine solution. It is necessary to wait for the disinfectant to dry completely, and carry out the manipulation without touching the skin treatment site.

After venipuncture, the remaining iodine should be removed from the surface of the skin to avoid burns.

Until transport from the purpose of bacteriological research the sample, together with the direction, is stored at room temperature (no more than 2 hours) or in a thermostat.

Rules for obtaining venous blood for PCR studies

Blood sampling should be done on an empty stomach or 3 hours after a meal from the cubital vein in a sitting position. Blood sampling is carried out in test tubes with anticoagulant (EDTA).

Immediately before venipuncture, the skin at the venipuncture site is disinfected by circular movements from the center to the periphery twice with 70% alcohol solution or 1-2% iodine solution. It is necessary to wait for the disinfectant to dry completely, and carry out the manipulation without touching the skin treatment site. After venipuncture, the remaining iodine should be removed from the surface of the skin to avoid burns.

After taking blood, the tube should be gently turned upside down several times so that the blood in the tube is thoroughly mixed. Place the test tube in a tripod.

Until transport to the laboratory for the purpose of PCR research the sample together with the referral is stored at a temperature of 20 - 25 °C for 6 hours from the moment of receipt of the material - for the quantitative determination of nucleic acids, and for 12 hours - for the qualitative determination of nucleic acids; at a temperature of 2 - 8 °C - no more than one day for the qualitative and quantitative determination of DNA / RNA of infectious objects. Freezing of whole blood samples is not acceptable.

Rules for obtaining pleural fluid for bacteriological and PCR studies

Take the material in disposable, tightly screwed test tubes with a volume of 10 - 15 ml.

Before manipulation, the skin is disinfected with 70% ethyl alcohol, then with 1-2% iodine solution, excess iodine is removed with a gauze cloth moistened with 70% alcohol to avoid burning the patient's skin. After this, percutaneous aspiration is performed to obtain a sample of pleural fluid with careful observance of the rules of asepsis. The sample volume must be at least 5 ml. All air bubbles are removed from the syringe, after which the sample is immediately transferred to a sterile plastic container. The container is tightly closed with a lid.

Until the moment of transportation, the sample along with the direction for bacteriological examination stored in a refrigerator at a temperature of 4 - 8 ° C. The duration of storage of pleural fluid at room temperature should not exceed 2 hours.

For PCR studies it is allowed to store the sample for 1 day at a temperature from 2 to 8 °C, for a longer time - at a temperature not higher than -16 °C.

Bronchoscopy is performed under conditions of oxygen therapy (oxygen inhalation through nasal catheters, using a Venturi mask or a mask with a reservoir). If adequate blood oxygenation cannot be achieved, bronchoscopy is performed under non-invasive ventilation. In mechanically ventilated patients, the procedure is performed under general anesthesia under conditions of myoplegia through a respirator adapter equipped with a valve for a bronchoscope. Bronchoalveolar lavage is carried out according to accepted rules. The fibrobronchoscope is carried into the bronchus until it is jammed, after which a 0.9% sodium chloride solution heated to 37 ° C is injected using disposable syringes 8 portions of 20 ml (150 - 160 ml). In order to prevent the collapse of the alveoli, suction is carried out at 50 - 80 mm Hg. Art. This procedure allows you to get the required number of alveolar macrophages, in which the causative agent of CAP is propagated.

In life lung tissue obtained by transbronchial biopsy using a bronchoscope, which allows to identify pneumocysts in 66 - 98%, however, this method of material sampling is not indicated for all patients. Obtaining material for research is also possible with open lung biopsy or with the help of percutaneous intrathoracic aspiration with a pulmonary needle in patients who are contraindicated for transbronchial biopsy in the progressive course of the disease. The method of open lung biopsy gives the best (100%) results and is equal in result to surgical intervention, while a sufficiently large amount of material for research is obtained and a false negative result is completely excluded.

Currently, clinics have begun to actively investigate bronchoalveolar lavage to detect cysts and trophozoites.

Posthumous material collected during the first day after the death of the patient, smears are prepared, imprints of the lung or smears from the foamy contents of the alveoli.

Rules for obtaining tracheal aspirate for PCR research

Manipulation is carried out on an empty stomach after brushing the teeth and rinsing the mouth with water. The patient is asked to take several deep breaths, holding the breath for a few seconds, then exhale forcefully. This contributes to the appearance of a productive cough and the cleansing of the upper respiratory tract from sputum. After attaching the mucus extractor through the tube-adapter to the suction, the catheter for collecting tracheal aspirate was inserted into the pharynx through the oral cavity. Due to irritation of the mucous membrane in the region of the glottis, a cough reflex is provoked and the tracheal contents are extracted through a sterile catheter (6th or 7th size) using suction. The volume of the tracheal aspirate should be at least 3-5 ml.

Rules for obtaining induced sputum for bacteriological and PCR studies

Before the procedure, patients receive salbutamol (children - 200 mcg) via a metered dose inhaler to prevent bronchospasm. Then, for 15 minutes, oxygen is supplied through a jet nebulizer (aerosol apparatus) at a rate of 5 l / min with 5 ml of a 5% sterile NaCl solution. After that, tapping is performed on the anterior and posterior walls of the chest in order to stimulate sputum discharge.

The patient is then asked to cough well and collect the discharge from the lower respiratory tract (not saliva!) into a sterile container. The volume of the sputum sample should be at least 3 ml for adults and about 1 ml for children.

If sputum is not coughed up, it is recommended to combine the procedure with subsequent tracheal aspiration to aspirate tracheal contents using standard suction using a sterile size 6 or 7 catheter.

Until the moment of transportation, the sample along with the direction for bacteriological examination stored in a refrigerator at a temperature of 4 - 8 ° C. The duration of storage of sputum at room temperature should not exceed 2 hours.

For PCR studies storage is allowed for 1 day at a temperature of 2 to 8 °C, longer - at a temperature not higher than -16 °C.

Rules for obtaining smears from the upper respiratory tract for PCR studies

The material is taken after rinsing the mouth with boiled water at room temperature. If the nasal cavity is filled with mucus, it is recommended to blow your nose before the procedure. Within 6 hours before the procedure, you can not use medications that irrigate the nasopharynx or oropharynx and drugs for resorption in the mouth.

Smears are taken from the patient with two different probes, first from the mucosa of the lower nasal passage, and then from the oropharynx, while the ends of the probes with swabs after taking the smears are sequentially placed in one tube with a volume of 1.5-2.0 ml with 0.5 ml of the transport medium.

Smears from the nasopharyngeal mucosa in children take a dry sterile nasopharyngeal velor swab on a plastic applicator. The probe is inserted with a slight movement along the outer wall of the nose to a depth of 2-3 cm to the lower concha, slightly lowered down, inserted into the lower nasal passage under the lower nasal concha, make a rotational movement and removed along the outer wall of the nose. The total depth of insertion of the probe should be approximately half the distance from the nostril to the ear opening (3 - 4 cm for children and 5 - 6 cm for adults). After taking the material, the end of the probe with a swab is lowered into a sterile disposable tube with a transport medium to the point of breaking, while the flexible part of the probe is coiled, then, covering the top of the tube with a lid, the handle of the probe is lowered down, achieving complete breaking off of the upper part of the probe. The tube is hermetically sealed.

Nasopharyngeal swabs in adults it is also permissible to take it with a dry sterile probe made of polystyrene with a viscose swab. The probe is inserted with a slight movement along the outer wall of the nose to a depth of 2-3 cm to the lower concha, slightly lowered down, inserted into the lower nasal passage under the lower nasal concha, make a rotational movement and removed along the outer wall of the nose. The total depth of insertion of the probe should be approximately half the distance from the nostril to the ear opening (5 cm for adults). After taking the material, the end of the probe with a swab is lowered to a depth of 1 cm into a sterile disposable tube with a transport medium and broken off, holding the tube cap. The tube is hermetically sealed.

Swabs from the oropharynx take a dry sterile polystyrene probe with a viscose swab with rotational movements from the surface of the tonsils, palatine arches and the posterior wall of the oropharynx, gently pressing the patient's tongue with a spatula. After taking the material, the working part of the probe with a swab is placed in a sterile disposable tube with a transport medium and a probe with a swab from the nasopharynx. The end of the probe with a swab (1 cm) is broken off, holding the lid of the test tube so that it allows you to tightly close the test tube. It is allowed to store for three days at a temperature of 2 - 8 °C, for a longer time - at a temperature not higher than -16 °C.

Rules for obtaining material for serological diagnostics
(Detection of specific antibodies)

Serological testing (determination of antibodies) requires two samples of blood serum, the 1st sample is taken on the day of the initial diagnosis, the 2nd sample - 2-3 weeks after the first one. Blood is taken from a vein in a volume of 3-4 ml, or from the third phalanx of the middle finger in a volume of 0.5-1.0 ml into a disposable plastic tube without anticoagulant. Blood samples are left at room temperature for 30 minutes or placed in a thermostat at 37 °C for 15 minutes. After centrifugation (10 min at 3,000 rpm), the serum is transferred into sterile tubes using a separate tip with an aerosol barrier for each sample. Shelf life of whole blood - no more than 6 hours, freezing is unacceptable. Shelf life of blood serum at room temperature - for 6 hours, at a temperature of 2 - 8 ° C - for 5 days, for a longer time - at a temperature not higher than -16 ° C (multiple freezing / thawing is unacceptable).

Rules for obtaining autopsy material for PCR research

The post-mortem material is collected during the first day after the death of the patient with a sterile individual instrument (individually for each organ) from the area of ​​damaged tissue with a volume of 1-3 cm 3, placed in disposable sterile plastic containers with a hermetically screwed lid, frozen and stored at a temperature not higher than -16 °C.

Rules for obtaining and transporting urine to determine the antigen of legionella or pneumococcus

Urine samples for research with a volume of 5–10 ml are placed in standard plastic containers and stored at room temperature (15–30 °C) for no more than 24 hours after sampling before setting up the reaction. If necessary, specimens can be stored at 2-8°C for up to 14 days or at -20°C for extended periods for initial or re-examination. Boric acid can be used as a preservative. Before setting the reaction, chilled or frozen urine samples are examined for the presence of antigen after reaching room temperature.

Material labeling requirements for laboratory testing

The label of test tubes (containers) with the material indicates: the last name and first name of the subject, the date of taking the material, the type of material.

In the accompanying document (referral) to the material collected for research in the laboratory, it is necessary to indicate:

Name of the institution that sends the material for research, and telephone number;

Surname and name of the examined patient;

Age;

Date of illness or contact with the patient;

Proposed diagnosis, severity of disease or reason for examination;

The severity of the disease;

Data on vaccination against influenza in the current epidemic season (vaccinated / not vaccinated / not available);

Date and signature of the medical person.

Material transport produced in thermal containers at the recommended storage temperature. Samples from each patient are additionally packaged in an individual sealed bag with absorbent material.

Processing of biological material before laboratory testing

In the laboratory, before starting PCR studies of biological material of a viscous consistency (sputum, aspirates from the trachea), it is necessary to pre-treat it in order to reduce the viscosity, for example, using a drug such as Mucolysin, according to the instructions. The autopsy material is subjected to homogenization followed by the preparation of a 20% suspension using a buffer solution (physiological sodium chloride solution or phosphate buffer).

Bibliography

1. Community-acquired pneumonia in adults: practical recommendations for diagnosis, treatment and prevention: A guide for doctors / A.G. Chuchalin, A.I. Sinopalnikov et al. M., 2010. 106 p.

2. Pneumonia /A.G. Chuchalin, A.I. Sinopalnikov, L.S. Strachunsky. M., 2006.

3. Standard for specialized medical care for severe pneumonia with complications: Appendix to the order of the Ministry of Health of Russia dated January 29, 2013 No. 741n.

4. Kozlov R.S. Pneumococci: lessons from the past - a look into the future. Smolensk, 2010.

5. SP 3.1.2.2626-10 "Prevention of legionellosis".

6. SP 3.1.7.2811-10 "Prevention of coxiellosis (Q fever)".

7. SP 3.1.7.2642-10 "Prevention of tularemia".

8. SP 3.1.7.2815-10 "Prevention of ornithosis".

10. MU 3.1.2.3047-13 "Epidemiological surveillance of community-acquired pneumonia".

11. MU 4.2.2039-05 "Technology for the collection and transportation of biomaterials to microbiological laboratories" (approved by the Chief State Sanitary Doctor of the Russian Federation on December 23, 2005).

12. Guidelines of the Ministry of Health of the Russian Federation No. 99/168 "Organization of the detection of patients with tuberculosis using radiation, clinical and microbiological methods." 2000.

13. MU 1.3.2569-09 "Organization of the work of laboratories using nucleic acid amplification methods when working with material containing microorganisms of I-IV pathogenicity groups."

14. MU 2.1.4.1057-01 "Organization of internal quality control of sanitary and microbiological studies of water".

15. MP No. 01/14633-8-34 “Detection of antigen of bacteria Legionella pneumophila serogroup 1 in clinical material by immunochromatographic method” (approved by the Chief State Sanitary Doctor of the Russian Federation on December 9, 2008).

16. MUK 4.2.1890-04 "Determination of the sensitivity of microorganisms to antibacterial drugs" (approved by the Chief State Sanitary Doctor of the Russian Federation on 4.03.2004).

Editor

Doctor, forensic expert

Pneumonia is accompanied by severe symptoms, can provoke the development of serious complications and even lead to death. For this reason, it is very important to see a doctor in time to undergo a diagnosis and make an accurate diagnosis.

Diagnosis is a paramount task in the treatment of the disease, since there are many causative agents of the disease. The success of the treatment depends on the results of the diagnosis.

Symptoms and criteria for pneumonia in adults

The foundation on which the process of diagnosing pneumonia is based is the clinical picture of the disease. Knowing, the patient may suspect something is wrong and consult a doctor.

At the same time, the specialist needs to describe the clinic of the disease as accurately as possible, because this will help to formulate the features of the course of the pathological process and in the future will help in the treatment.

The symptomatology of pneumonia largely depends on the nature, form and type of the disease, but if we consider the criteria that are present in the development of pneumonia in most cases, they are as follows:

1. Cough, which does not go away for a long time, even when taking antitussives. Initially, the cough is dry, then becomes wet and is accompanied by an accumulation of poorly expectorated sputum.
2. Respiratory dysfunction- is expressed in the appearance of shortness of breath even in the absence of stress, a decrease in the "working" volume of the lungs.
3. Feverish state- there is an increase in body temperature to high values ​​\u200b\u200b(38.5-39 ° C).
4. Body intoxication- typical signs of this condition are weakness, fatigue, drowsiness.
5. A striking sign of the development of pneumonia are the so-called bronchial breathing, the appearance of pleural noises, wheezing during inhalation and exhalation, as well as voice trembling.
6. Also, inflammation of the lungs manifests itself chest pain localized in the area of ​​inflammation.

Depending on the nature of the course of the disease, the type of pathogen and other factors, the clinical picture may change. That's why important pay attention to any deviations from the norm, and a detailed examination will help identify pneumonia.

Differential Diagnosis

The principle of differential diagnosis is based on a comparison of diseases that are similar in clinical signs. After that, diseases are excluded, in the clinical picture of which there are no symptoms present in the patient at the moment.

Thus, it is possible to significantly reduce the range of probable diseases, after which it will be much easier to make the correct diagnosis, or even the only correct answer will remain.

The differential diagnosis of pneumonia is done in the following order:

1. The most detailed acquaintance with the patient's condition, finding out all the symptoms present and monitoring the development of the pathology. Based on the current clinical picture, the maximum number of diseases that somehow fit symptomatically is selected.
2. Diseases are related, in descending order from most likely to least likely.
3. The least appropriate diagnoses are discarded and the most probable diseases are compared with the symptoms that reflect the current picture of the patient's illness.

For example, let's make a brief differential diagnosis of pneumonia, differentiating this disease with some other pathologies, and for ease of perception, we will compile a small table:

The presented table gives only a superficial assessment of the comparison of pneumonia and the mentioned diseases. In fact, the same tuberculosis or bronchitis is very similar to pneumonia, and with dif. The diagnosis takes into account not only the symptoms, but also data from blood tests, fluorography and other examination methods.

Methods

Taking into account the complexity of pneumonia as a disease, a lot of factors in its development, a huge number of types of pathogens, it is impossible to single out the most informative diagnostic method with certainty. An integrated approach is important This applies to both methods of diagnosis and treatment. Consider the most popular methods for diagnosing pneumonia.

Auscultation and percussion

The techniques are used during the initial examination of the patient by a doctor along with the collection of anamnesis, as well as at each subsequent examination. They are necessary at all stages of the disease and are the gold standard in determining the majority of pathologies affecting the respiratory organs and respiratory tract.

To understand the principle of each method, consider them separately:

- with the help of a phonendoscope, a stethoscope, or even by applying the ear to the patient's body, the doctor listens to the sounds that occur during the functioning of the lungs.

The development of pneumonia is evidenced by various wheezing, whistling or gurgling sounds. In this case, the doctor gets the opportunity to determine the localization of the focus of inflammation, the degree of neglect of the disease, and in some cases even identify the type of pathological process.

- percussion examination involves tapping the surface of the human body for the subsequent assessment of the sounds that arise during this. The principle of percussion is that the organs of our body have different densities. Moreover, with the development of the inflammatory process and associated pathological changes, the density changes, and with it the sound received from tapping.

The development of pneumonia is indicated by dull and "shortened" sounds. Percussion allows not only to suspect the development of pneumonia, but also to determine the localization of the focus.

Palpation with pneumonia is to determine the voice trembling. During a conversation, vibrations from the vocal cords through the air entering the lungs are transmitted to the chest wall. The doctor symmetrically in different projections of the lungs puts his palms and palpates the chest. The patient must pronounce words with the letter "r". On palpation, the specialist compares the voice trembling on the right and left, normally it is moderate and symmetrically expressed.

Lobar, focal pneumonia is characterized by increased trembling over the affected lobe or area. If the foci of pneumonia are small, it is difficult to determine the change in voice trembling.

x-ray

One of the most informative and mandatory ways to diagnose pneumonia in adults. - a method of research in which a special apparatus is used that emits x-rays. The latter pass through different body structures in different ways, as they differ in their density characteristics.

When x-rays pass through inflammation in the lung tissue, it looks like blackouts on the x-ray image. To complete the picture and increase the information content of the study, an X-ray of the lungs is done in the lateral and direct projection. In order to clarify the diagnosis, it is possible to focus the radiation on a specific area in order to get a more detailed “picture”.

Fluorography

Another method of radiation diagnostics, the principle of which is similar to the previous one, since X-rays are used in the technology, and the result of the study is a picture of the lungs.

The image also shows the foci of the inflammatory process, displayed as blackouts. However, the results are less detailed because the image is reduced in size.

is a mass method of examination aimed at confirming the development of pneumonia or excluding pathology. In other words, if there is a suspicion of the development of pneumonia, the patient is referred for fluorography. When the concerns are confirmed, more informative diagnostic methods are selected.

Laboratory research

The category includes diagnostic methods, for which various biomaterial is taken with its subsequent study. The following research methods play an important role in the diagnosis of pneumonia:

• - gives information about the content of erythrocytes, leukocytes, lymphocytes, hemoglobin concentration in the blood. Certain deviations from the norm indicate an inflammatory process in the body and even indicate oxygen starvation, which manifests itself in pneumonia.
• - assessment of metabolic processes in the body, the study indicates malfunctions in the functioning of organs (in this case, the lungs). Also, this analysis gives an idea of ​​the presence of pathological flora in the body.
• General urine analysis- with inflammation of the lungs, urine changes its chemical composition. Impurities and sediment appear in it, the protein concentration increases, which indicates the presence of an inflammatory process.
• - the main purpose of the analysis is to identify and determine the type of pathogen that caused the development of pneumonia. The results allow not only to determine the nature and type of the pathological process, but also to select the most appropriate antibiotics to combat pneumonia.

Bronchoscopy

Bronchoscopy is an additional method for diagnosing pneumonia. The procedure consists in an invasive examination of the trachea and bronchi, assessment of their condition. During the study, material is taken for histological examination, it is possible to detect and remove foreign bodies (if any).

Also, through bronchoscopy, a specialist gets the opportunity to diagnose anomalies in the structure of the lungs, bronchi or detect inflammation, an oncological neoplasm in the area under study.

CT and MRI

The most informative diagnostic methods for various diseases available today. Both methods can be used as a study of the lungs in the development of pneumonia, but the principle of their action is fundamentally different:

• CT or computed tomography– a more advanced alternative to radiography. X-rays are also used in CT, but this research method is much more effective, it makes it possible to study in detail the structure of the lungs and bronchi. For these reasons, CT is used in cases where classical x-rays have not yielded enough results.
• MRI or magnetic resonance imaging- The principle of this type of research is based on the use of a magnetic field that is formed under the influence of a huge magnet. The tomograph displays a three-dimensional image of the organ, which makes it possible to study in detail the state of the latter, as well as the degree of progression of pneumonia, and much more.

Good to know! CT and MRI are the best ways to get a complete justification of the diagnosis, when previous examination methods have not given a full picture. Also, during the examination of the lungs, CT and MRI make it possible to clarify the condition of the heart, the functions of which are affected by pneumonia.

Useful video

The doctor talks about how to differentiate pneumonia and not confuse it with other diseases:

Conclusion

A complete diagnosis plays an important role in the diagnosis and control of the disease. Only having an idea of ​​the extent of damage to the lung tissue, the degree of progression of pneumonia, the type of pathology, the type of pathogen and other data, you can choose the most effective method of treatment.