Clinical classification and types of acute pneumonia. General features of pneumonia, classification. Classification of pneumonia

For quotation: Nikonova E.V., Chuchalin A.G., Chernyaev A.L. PNEUMONIA: EPIDEMIOLOGY, CLASSIFICATION, CLINICAL AND DIAGNOSTIC ASPECTS // Breast cancer. 1997. No. 17. S. 2

The article presents modern data on the epidemiology of pneumonia, morbidity and mortality rates among various age categories of the population both in our country and abroad. The characteristics of various factors predisposing to the occurrence of pneumonia are given, and their role in the development of severe disease and mortality is determined. A modern classification according to the international agreement on pneumonia is presented. The etiological characteristics of community-acquired and nosocomial pneumonia are given, and the role of etiological diagnosis in making a diagnosis is highlighted. The issue of correct diagnosis of pneumonia is discussed, information is provided on the frequency of under- and overdiagnosis, and their causes are indicated. The clinical and radiological picture is described and the basic principles of treatment of pneumonia are given.

The paper presents the currently available data on the epidemiology of pneumonia, morbidity and mortality in different age groups in our and foreign countries. It also characterizes various factors predisposing to pneumonia, defines their contribution to their severity and death. The paper gives the present-day classification according to the international agreement on pneumonia, outlines out hospital and inhospital pneumonias, covers the role of etiological diagnosis in establishing the diagnosis of the disease. It also discusses whether the diagnosis of pneumonia is made correctly, provides data on the frequency of hypo- and hyperdiagnosis, indicates their reasons. The clinical and X-ray of the disease are outlined and the basic principles in the treatment of pneumonia are given.

Research Institute of Pulmonology, Ministry of Health of the Russian Federation, Moscow
A. G. Chuchalin - Director of the Research Institute of Pulmonology of the Ministry of Health of the Russian Federation, Academician of the Russian Academy of Medical Sciences, Professor
A. L. Chernyaev - head. Laboratory of Pathological Anatomy, Research Institute of Pulmonology, Ministry of Health of the Russian Federation, Professor, Doctor of Medicine. sciences
E. V. Nikonova - graduate student of the Research Institute of Pulmonology of the Ministry of Health of the Russian Federation
Research Institute of Pulmonology, Ministry of Health of the Russian Federation, Moscow
Prof. A. G. Chuchalin, Academician of the Russian Academy of Medical Sciences, Director, Research Institute of Pulmonology, Ministry of Health of the Russian Federation
Prof. A. L. Chernyaev, MD, Head, Laboratory of Pathoanatomy, Research Institute of Pulmonology, Ministry of Health of the Russian Federation
Yes. V. Nikonova, Postgraduate Student, Research Institute of Pulmonology, Ministry of Health of the Russian Federation

P Neumonia is one of the most common diseases, occurs at any age, and has certain course characteristics in different age periods. It is a complex of pathological processes developing in the distal parts of the lung tissue. The main manifestation of these processes is infectious, exudative, and less often interstitial inflammation, caused by microorganisms of various natures, and dominant in the entire picture of the disease. From a clinical point of view, the concept of “pneumonia” should be defined as an infectious disease of the lower respiratory tract, confirmed x-ray.

Epidemiology of pneumonia

Modern ideas about pneumonia were formed as a result of their centuries-long study. Hippocrates also described pneumonia, its symptoms and treatment. Ancient authors said that a number of successive stages can be distinguished in the development of pneumonia. The question of the beginning and primary source of development has remained unresolved to this day, although it seems obvious that the primary source of pneumonia as an infectious disease is its etiological factor - a pathogenic pathogen.
The epidemiology of pneumonia at the present stage is characterized by a trend towards an increase in morbidity and mortality, both in our country and throughout the world, that has emerged since the late 80s. In developed countries, the incidence of pneumonia ranges from 3.6 to 16 per 1000 people. Currently, throughout the world, pneumonia ranks 4th - 5th in the structure of causes of death after cardiovascular pathology, cancer, cerebrovascular pathology and chronic obstructive pulmonary diseases (COPD), and among infectious diseases it ranks 1st. In the United States, 3-4 million people fall ill with community-acquired pneumonia annually, 30-40% of them require hospitalization. Approximately 50 - 70% of patients are treated as outpatients, and the mortality rate among them is only 1 - 5%.
The incidence in the age group over 60 years is from 2 0 to 44 per 1000 population per year. The mortality rate from pneumonia in this category of patients is 10 - 33%, and in pneumonia complicated by bacteremia it reaches 50%. The mortality rate from pneumonia is high among newborns and young children and reaches 25% in children under 5 years of age. According to WHO, the mortality rate of children under 1 year in our country is 2-4 times higher (25.1 per 1000 population) than in other economically developed countries.
Great importance is attached to hospital-acquired (nosocomial) pneumonia. It accounts for approximately 10 - 15% of all hospital-acquired infections. The mortality rate for nosocomial pneumonia ranges from 30 - 60 to 80%.
Among patients with pneumonia, men predominate. They constitute, according to many authors, from 52 to 56% patients, while women - from 44 to 48%.
The incidence of pneumonia clearly increases with age. Patients aged 40 to 59 years make up 38.4 - 55.7% of cases, over 60 years old - from 31 to 60%.
The duration of temporary disability is on average 25.6 days and can range from 12.8 to 45 days. According to foreign authors, the average number of bed days for patients over 60 years of age is 21.

Risk factors for pneumonia

In the occurrence of pneumonia, predisposing factors, or risk factors, leading to damage to one or more protective mechanisms play a significant role. Most often, pneumonia occurs in the cold season, i.e. the incidence is seasonal, but it should be noted that the disease can occur at any time of the year. One of the most common provoking factors is hypothermia. Viruses are of great importance in the occurrence of pneumonia, especially during influenza epidemics, most often these are influenza viruses A, B, C, parainfluenza, adenoviruses, respiratory syncytial viruses and coronaviruses. Age over 60 years is another important risk factor, which is primarily associated with suppression of the cough reflex, impaired mucociliary clearance, and changes in microbial flora. In addition, at this age, a risk factor is the presence of COPD, pathology of the cardiovascular system, kidneys, and gastrointestinal tract. Another important factor is smoking: smoking up to 15 - 20 cigarettes per day leads to impaired mucociliary clearance, increased chemotaxis of macrophages and neutrophils, their activation, destruction of elastic tissue, and decreased effectiveness of mechanical protection. The occurrence of pneumonia is predisposed by disturbances of consciousness, alcohol intoxication, brain injury, epileptic seizure, anesthesia, overdose of sleeping pills and narcotics. In all these cases, aspiration of the contents of the oropharynx and gastrointestinal tract, carrying large quantities of various aerobic and anaerobic flora, can occur. Pneumonia can also develop in the postoperative period, primarily through operations on the chest and abdominal organs; in this case, nosocomial pneumonia occurs, the frequency of which ranges from 20 to 50%, and the mortality rate ranges from 19.2 to 80%. A big problem is the occurrence of pneumonia in patients on mechanical ventilation (ALV) for more than a day. At the same time, the probability of nosocomial pneumonia is extremely high, its frequency ranges from 13 to 55%.
Primary and secondary immunodeficiency plays an important role in the occurrence of pneumonia. The main contingent is patients with various tumor diseases: hematological malignancies, myelotoxic agranulocytosis, autoimmune diseases, patients receiving chemotherapy, radiation, immunosuppressive therapy, drug addiction and AIDS. The main pathogens are opportunistic, gram-negative flora, fungi (often Aspergillus spp.), Pneumocystis, cytomegalovirus, Noca rdia. One cannot fail to mention pneumonia in severe neutropenia caused by the use of chemotherapy for malignant neoplasms, the causative agents of which are both gram-positive cocci and gram-negative flora. Against the background of these pneumonias, septic conditions develop; the mortality rate is high. Risk factors for pneumonia may also include contact with birds, rodents, and travel.

Classification of pneumonia

The current division of pneumonia according to the clinical and pathomorphological principle into parenchymal - lobar and focal, as well as the identification of interstitial and mixed pneumonia is not very informative in terms of choosing the optimal etiotropic therapy. Recent advances in microbiology, pulmonology and pharmacotherapy dictate the need to develop the concept and classification of various types of pneumonia. The division of pneumonia should be based on the etiological principle, which will allow for targeted etiotropic pathogenetic treatment. Today, within the framework of the European Society of Pulmonologists and the American Thoracic Society, a discussion continues on the issue of classification of pneumonia. To streamline diagnostic methods and especially treatment methods, a clinical classification of pneumonia is recommended. There are four forms of pneumonia:

community-acquired (home-acquired);
in-hospital (nosocomial);
against the background of immunodeficiency states;
atypical pneumonia.

This classification reflects not only the place of origin of the disease, but also significant features (epidemiological, clinical and radiological), and most importantly - a certain range of pathogens, the course, outcome and treatment programs for patients with pneumonia. In foreign classifications and in periodical literature, pneumonia is divided into primary (community-acquired) and secondary (nosocomial-acquired).
Recently, medical practice requires greater detail of pneumonia, taking into account their diversity and wide range of pathogens. It is necessary to distinguish between aspiration pneumonia, post-traumatic pneumonia, postoperative pneumonia, pneumonia developing against the background of COPD, chronic alcoholism, malignant neoplasms, immunodeficiency, and nosocomial pneumonia. Risk factors for the occurrence of pneumonia of the latter group are the presence of patients on mechanical ventilation, the presence of a tracheostomy, the postoperative period, and massive antibacterial therapy.
Of great importance is the grouping of pneumonia by severity, which makes it possible to identify patients in need of intensive care, outline the most rational therapy, and assess the prognosis. The main clinical criteria for the severity of the disease are the degree of respiratory failure, the severity of intoxication, the presence of complications, and decompensation of concomitant diseases.

Etiology of pneumonia

The etiological approach in diagnosing pneumonia is extremely important. A practicing doctor almost always has to prescribe antibacterial therapy to a patient, not only in the absence of verification of the pathogen in the first days, but also without any prospects for obtaining microbiological data about the pathogen. The first publicly accessible and mandatory step is to establish a presumptive etiological diagnosis based on clinical and epidemiological data, taking into account the etiological structure of modern pneumonia. Of great importance for the diagnosis of pneumonia upon admission of a patient to a hospital is Gram staining of a sputum smear, which makes it possible to identify gram-positive and gram-negative pathogens, intracellular and extracellular localization of microorganisms. Comparison of bacterioscopy data with clinical and radiological features makes it possible to make an early clinical and bacteriological diagnosis in 86% of all patients with pneumonia and in 70% of patients with pneumococcal pneumonia. When diagnosing pneumonia, bacteriological examination of sputum (culture on media) and determination of sensitivity to antibiotics, identification of pathogens by a quantitative method in diagnostically significant titers (10 6 microbial cells or more in 1 ml of sputum) are important. Abroad, along with the study of sputum, studies of aspirate, washings obtained during fiberoptic bronchoscopy, materials obtained during transtracheal aspiration, blood culture, and determination of antibodies to antigens of various pathogens in blood serum are widely carried out. The division of pneumonia into community-acquired and nosocomial is justified primarily by differences in the etiological structure. In the occurrence of community-acquired pneumonia, the leading role belongs to Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus occupies a certain place. The occurrence of community-acquired pneumonia can also be caused by atypical pathogens: Mycoplasma pneumoniae, Legionella pneumophilla and Chlamydia pneumoniae.
In the occurrence of nosocomial pneumonia, the role of opportunistic and gram-negative flora is great. This is primarily S. aureus, the occurrence of which ranges from 2.7 to 30%. The pathogen of the Enterobacteriacea family, Klebsiella pneumoniae, accounts for from 9.8 to 1 2.6% of pneumonia, with mortality ranging from 40 to 71%. The specific gravity of E.coli ranges from 17.3 to 32.3%, Proteus vulgaris - from 8.2 to 24%. Pseudomonas aeruginosa is responsible for the development of nosocomial pneumonia in 17% of cases, mortality reaches 80%. The share of Legionella pneumophilla as the causative agent of nosocomial pneumonia reaches 33%.
The role of viral pneumonia increases during epidemics of influenza A, B and ranges from 8.6 to 35%. The presence of purely viral pneumonia is not recognized by all authors. It is believed that they are conductors who prepare the “soil” for the addition of bacterial and mycoplasma flora.
The relevance of the problem of mixed infections in recent years is determined primarily by the fact that they account for up to 30 - 50% of cases of the disease, monoculture occurs in 40.5 - 50% of cases.
The etiology of pneumonia in more than 50% of cases cannot be established at all. The reasons are most often the following:

lack of microbial research;
improper collection of material;
pathogen unknown;
previous treatment with antibiotics (before taking material);
uncertain clinical significance of the isolated pathogen;
use of an inadequate treatment method.

Diagnosis of pneumonia

There is the concept of a “gold standard” in the diagnosis of pneumonia, which includes the assessment of five signs: fever, cough, sputum, leukocytosis and radiologically detectable infiltrate. However, following only this standard leads to diagnostic errors.
Despite significant advances in the study of pneumonia, the synthesis of new antibacterial drugs, their wide selection, and the expansion of the range of laboratory diagnostics, the level of correct diagnosis of pneumonia remains insufficient.
The frequency of overdiagnosis of pneumonia ranges from 16 to 55%, and underdiagnosis - from 2.2 to 30.5%. The most common discrepancies in diagnoses are in clinics. An analysis of materials dating back to the 70s showed that a complete coincidence of the outpatient diagnosis with the clinical diagnosis is observed in only 20% of cases.
It should be noted that one of the important reasons for untimely diagnosis is the late seeking of medical care by patients both at the pre-hospital and hospital stages.
Underdiagnosis of pneumonia is largely due to defects in x-ray examination - both x-ray underdiagnosis and the lack of lung x-rays. Although we must not forget about the so-called X-ray negative pneumonia, which accounts for accounts for about 20%.
The situation is poor with differential diagnosis between influenza and pneumonia, while influenza and acute respiratory infection are mistakenly diagnosed instead of pneumonia. This is most often observed at the prehospital, outpatient stage, especially during influenza epidemics. Pneumonia, which occurs in various severe concomitant diseases: COPD, cardiovascular, cerebrovascular, oncological diseases, as well as in weakened and elderly patients who abuse alcohol. The severity and danger of death from pneumonia is not given due importance.
In hospital patients over 60 years of age, errors in diagnosing pneumonia are associated with concomitant pathology, since in this case extrapulmonary symptoms come to the fore, such as cardiovascular failure, impaired consciousness, exacerbation and decompensation of concomitant diseases.
Daily mortality in hospital ranges from 6 to 1 4% . Incorrect interpretation of the clinical picture can also occur in young patients and in patients under 50 years of age. Myocardial infarction (5.1%), acute abdomen (3.1%), acute cerebrovascular insufficiency (7.1%), and other diseases (29.6%) are often diagnosed.
Reliable etiological diagnosis is currently difficult. Epidemiological, clinical, X-ray laboratory criteria, of course, in a number of cases allow, with varying degrees of probability, the etiological diagnosis of pneumonia, but cannot serve as the basis for a reliable conclusion about the agent. Often in Russian hospitals, sputum bacterioscopy is not performed, which makes it possible to determine gram-positive and gram-negative flora; bacteriological control is poorly developed and practically absent in urgent situations. Often sputum examination is not performed and treatment usually remains empirical. Due to erroneous diagnosis of pneumonia, antibacterial therapy is either started late or it is inadequate to the clinical picture, which also leads to the development of complications and increased mortality.
Subjective and objective reasons for errors in the diagnosis of pneumonia are identified.
Subjective reasons include:

loss of clinician interest in patients over 60 years of age;
negligence and haste during the examination;
illogical understanding of the obtained clinical and laboratory data;
overestimation and underestimation of research methods, consultations with specialists;
lack of a survey system and poor knowledge of survey methods;
ignoring or inept use of medical history data;
incorrect and incomplete formulation of the final diagnosis.

Objective reasons include:

severity of the patient's condition;
lack of time for correct diagnosis;
atypical course of the disease;
limited medical capabilities.

If it is true that no kind of human activity can do without mistakes, then this is also true for healing. According to I.V. Davydovsky (1928), “medical errors” are a type of conscientious errors made by a doctor in his judgments and actions when performing special medical duties. Despite the enormous achievements of modern therapy, the rule remains: “bene diagnostitur, bene curatur” - without a good diagnosis there cannot be a high level of the treatment process. It must be said that an exhaustively collected anamnesis allows one to establish the correct diagnosis in 50% of cases, while a clinical examination - in 30%, additional research - in 20% . A diagnosis made based on clinical data is often a presumptive diagnosis that requires confirmation. Diagnostic errors reduce the effectiveness of treatment and in 30 - 40% lead to a protracted course of pneumonia.

Clinical course of pneumonia

The clinical picture of pneumonia is determined by the characteristics of the pathogens and the state of the macroorganism. The main manifestations include various combinations of bronchopulmonary and extrapulmonary symptoms. Bronchopulmonary symptoms include cough, shortness of breath, chest pain, sputum production, which can be mucous, mucopurulent, and sometimes bloody. Dullness of percussion sound, weakened vesicular and bronchial breathing, crepitus, and pleural friction noise are also determined. Extrapulmonary include hypotension, weakness, tachycardia, chills, myalgia, fever, confusion, meningism, changes in peripheral blood parameters. In some patients, mainly in weakened and elderly patients, as well as in the presence of severe concomitant pathology, extrapulmonary symptoms prevail over bronchopulmonary ones.
The clinical and radiological picture of pneumonia depends primarily on the etiological agent. The division of pneumonia according to etiology is of fundamental importance for determining the course, prognosis and treatment. Diagnosis of pneumonia is based primarily on establishing the presence of pneumonia as an independent nosological form: analysis of clinical and radiological data with mandatory consideration of the etiological characteristics of the inflammatory process. When diagnosing this nosology, the doctor must make a differential diagnosis with a number of diseases that have syndromic-similar symptoms, but differ in essence and require different treatment. The doctor has to solve the following differential diagnostic problems:

distinguishing pneumonia from extrapulmonary diseases;
differentiation of pneumonia from other respiratory diseases;
differentiation of pneumonia according to various criteria (etiology, extent of the process, complication).

Pneumonia should be distinguished from diseases of the cardiovascular system, pulmonary embolism, viral infection, chronic nonspecific lung diseases, tuberculosis, lung cancer, interstitial lung diseases, pneumonitis with systemic vasculitis, drug-induced lung damage, atelectasis, infarction and pulmonary contusion.
With pneumonia, recovery occurs within up to 4 weeks. Clinical criteria for recovery are considered to be the normalization of the patient’s well-being and condition, the disappearance of physical and radiological signs of inflammation, and the normalization of blood counts. However, often the dynamics of clinical signs of recovery do not agree with the X-ray picture of the lungs. It may take from 3 weeks to 6 months to restore the structure of the lung tissue. The prolonged course of pneumonia is characterized by the absence of normalization of the clinical and radiological picture within 4 weeks.

Treatment of pneumonia

It seems necessary to discuss the issue of where to treat a patient with pneumonia. According to the current situation in our country, this diagnosis is a mandatory indication for hospitalization of the patient. This position is controversial. In foreign guidelines, inpatient treatment of community-acquired pneumonia is reserved for patients with severe disease, in the presence of complications, bilateral lesions, serious concomitant diseases, for elderly patients, as well as for situations where there is no effect of treatment or there are social indications for hospitalization. The basis for the treatment of pneumonia is rational antibacterial therapy.
Treatment should begin without waiting for the results of a microbiological study, i.e. empirically. Upon receipt of bacteriological data, treatment is adjusted if it is insufficiently effective.
When choosing antibacterial drugs, one should take into account: the type of pathogen (probable, determined by clinical data), the severity of the disease, the potential toxicity of the drugs and possible contraindications. In addition, it is necessary to take into account allergy history.

It is necessary to decide on the use of monotherapy or a combination of several antibacterial drugs.
It is very important to take into account the resistance of microbial flora to antibacterial therapy.
The dose and frequency of drug administration should be commensurate with the intensity of the pathological process.
The therapeutic effect of the drug should be monitored and possible adverse reactions should be monitored.
When choosing antibacterial treatment, it is advisable to also use the results of sputum examination using Gram staining.
The cost of the drug used cannot be ignored.

Thus, the treatment of pneumonia remains a pressing problem at the present stage of development of clinical medicine. Diagnosing pneumonia is still quite a difficult task, which dictates the need for continuous improvement of diagnostic and treatment methods, as well as advanced training for doctors of all specialties.

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Pneumonia is an acute inflammatory disease of the respiratory parts of the lungs, predominantly of bacterial etiology, characterized by intra-alveolar exudation. The diagnosis of “acute pneumonia” is not used in modern literature and is unnecessary, since the diagnosis of “chronic pneumonia” is pathogenetically unfounded and outdated.

The main causes of the disease according to WHO

The respiratory tract of adults and children is constantly attacked by pathogens, but local defense mechanisms in the form of immunoglobulin A, lysozyme and macrophages in healthy people prevent diseases from developing.

Risk factors for developing pneumonia, as defined by WHO in 1995, include:

old age - people over 60 years of age (due to suppression of the cough reflex, the reflex responsible for spasm of the glottis);
the period of newbornhood and infancy (the reason is the incomplete development of the immune system);
conditions accompanied by loss of consciousness (epilepsy, traumatic brain injury, anesthetized sleep, suicide attempts with sleeping pills or drugs, alcohol intoxication);
respiratory diseases (chronic bronchitis, emphysema, acute respiratory distress syndrome), smoking;
concomitant diseases that reduce the activity of the immune system (oncological diseases, systemic connective tissue diseases, HIV infection, etc.);
negative social and living conditions, malnutrition;
keeping the patient in a lying position for a long time.

Modern medicine evolves every day, scientists isolate new microorganisms and discover new antibiotics. Classifications of diseases are also undergoing various changes, which are aimed at optimizing the treatment of patients, triaging patients, and preventing the development of complications.

Currently, WHO identifies several types of pneumonia in adults and children, based on the etiology of the pathogen, localization of the process, timing and conditions of occurrence, and clinical categories of patients.

Classification according to ICD-10 (by forms and timing of occurrence)

Out-of-hospital - occurs at home or in the first 48 hours of stay in a medical institution. The course is relatively favorable, the mortality rate is 10-12%.
Hospital (nosocomial) – occurs after 48 hours of the patient’s stay in the hospital or if the patient has been treated in any medical institution for 2 or more days over the previous 3 months. In modern protocols, the World Health Organization (WHO) includes in this category patients with ventilator-associated pneumonia (who are on mechanical ventilation for a long time), as well as patients with pneumonia who are kept in nursing homes. It is characterized by a high degree of severity and mortality up to 40%.
Aspiration pneumonia - occurs when a large amount of oropharyngeal contents is swallowed by unconscious patients with impaired swallowing and a weakened cough reflex (alcohol intoxication, epilepsy, traumatic brain injury, ischemic and hemorrhagic strokes, etc.). Aspiration of gastric contents may cause a chemical burn of the mucous membrane of the respiratory tract with hydrochloric acid. This condition is called chemical pneumonitis.
Pneumonia developing against the background of immunodeficiencies, both primary (thymic aplasia, Bruton's syndrome) and secondary (HIV infection, oncohematological diseases).

Varieties by pathogen, severity and localization

Classification by pathogen:

Bacterial - the main pathogens are Streptococcus pneumonia, Staphylococcus aureus, Mycoplasmapneumonia, Haemophilus influenza, Chlamydiapneumonia.
Viral - often caused by influenza viruses, parainfluenza, rhinoviruses, adenoviruses, respiratory syncytial virus. In more rare cases, these may be measles, rubella, whooping cough viruses, cytomegalovirus infection, and Epstein-Barr virus.
Fungal - the main representatives in this category are Candida albicans, fungi of the genus Aspergillus, Pneumocystisjiroveci.
Pneumonia caused by protozoa.
Pneumonia caused by helminths.
Mixed - this diagnosis occurs most often with a bacterial-viral association.

Forms of pneumonia by severity:

light;
average;
heavy;
extremely heavy.

Types of pneumonia by localization:

Focal – within the acinus and lobule.
Segmental, polysegmental - within one or several segments.
Lobar (outdated diagnosis: lobar pneumonia) – within one lobe.
Total, subtotal - can cover the entire lung.

The inflammatory process occurs:

one-sided;
bilateral.

From birth to 3 weeks - the etiological agent of pneumonia (more often in premature infants) are group B streptococci, gram-negative bacilli, cytomegalovirus infection, Listeria monocytogenes.
From 3 weeks to 3 months - in most cases, children are affected by a viral infection (respiratory syncytial virus, influenza viruses, parainfluenza, metapneumovirus), Streptococcus pneumoniae, Staphylococcus aureus, Bordetellapertussis, Chlamydiatrachomatis (nasal infection).
From 4 months to 4 years - at this age, the susceptibility of children increases to group A streptococci, Streptococcus pneumoniea, viral infections (parainfluenza viruses, influenza viruses, adenoviruses, rhinoviruses, respiratory syncytial viruses, metapneumoviruses), Mycoplasmapneumoniae (in older children).
From 5 to 15 years - at school age, pneumonia in children is most often caused by Streptococcus pneumoniae, Mycoplasmapneumoniae, Chlamydiapneumoniae.

Clinical categories of patients with community-acquired pneumonia according to ICD-10

Forms of nosocomial inflammation according to WHO

Early - occur during the first 4-5 days from the moment of admission to the hospital, have a relatively favorable diagnosis, microorganisms are generally sensitive to antibiotic therapy.
Late - appear after 6 days of stay in a medical institution, the diagnosis in most cases is questionable or unfavorable, the pathogens are multi-resistant to antibiotics.

Criteria for severe disease

the appearance on the radiograph of “fresh” focal infiltrative changes in the lungs;
temperature over 38°C;
bronchial hypersecretion;
Pa O2/Fi O2 ≤ 240;
cough, tachypnea, locally auscultated crepitations, moist rales, bronchial breathing;
leukopenia or leukocytosis, band shift (more than 10% of young forms of neutrophils);
sputum microscopy reveals more than 25 polymorphonuclear leukocytes in the field of view.

SELECTED LECTURES ON INTERNAL DISEASES

– V courses of pediatric and medical-prophylactic faculties

Selected lectures on internal medicine: Textbook for IV and IV year medical students – V courses of pediatric and medical-prophylactic faculties / Ed. prof. Fazlyeva R.M. – Ufa: Publishing house of the State Educational Institution of Higher Professional Education “BSMU Federal Health Agency”, part I, 2006. – 262s.

The textbook presents lecture material in the discipline “Internal Medicine” for IV year students of the Faculty of Medicine in the specialties “General Medicine” and IV – V courses in the specialties “Pediatrics” and “Medical and Preventive Care”, compiled taking into account the work programs of the discipline, regulatory federal documents and the current curriculum.

For each section of the textbook, modern scientific data on the etiology, pathogenesis, clinical picture, methods of diagnosis, treatment and prevention of diseases of internal organs is presented.

Reviewers:

Head of the Department of Internal Medicine with a course of outpatient therapy, State Educational Institution of Higher Professional Education “Izhevsk State Medical Academy of the Federal Agency for Health and Social Development of the Russian Federation”, Doctor of Medical Sciences, Honored Doctor of Russia, Professor L.T. Pimenov

Head of the Department of Hospital Therapy with a Course of Transfusiology at Samara State Medical University, Doctor of Medical Sciences, Honored Doctor of Russia, Professor V.A. Kondurtsev

Recommended by the Educational and Methodological Association for Medical and Pharmaceutical Education of Russian Universities as a teaching aid for students studying in the following specialties: General Medicine – 060101, Pediatrics – 060103, Medical and preventive care – 06010 .

As a control material, standard test tasks recommended by VUNMC (2002) for the IGA of graduates of medical universities were used, adapted by the authors to the work program of the discipline and supplemented taking into account the regional component of the curriculum.

PNEUMONIA

Pneumonia (P) – an acute infectious disease of predominantly bacterial etiology, characterized by the formation of an inflammatory infiltrate in the lung parenchyma.

The definition of pneumonia emphasizes the acute nature of inflammation, so you don’t need to use the term “acute pneumonia” (in the ICD – 10 revision (1992) there is no heading “acute pneumonia”).

Epidemiology. The incidence of pneumonia is on average 1%, that is, every year one out of 100 people gets sick. This rate is significantly higher in children and people over 60 years of age. Men get sick more often than women. In a number of patients (up to 20%), pneumonia is not diagnosed, occurring under the guise of bronchitis or other diseases.

The average mortality rate from pneumonia is 1 – 5%, in severe forms of the disease reaches 40 – 50%. Among all causes of human death, pneumonia ranks 4th after cardiovascular diseases, malignant neoplasms, injuries and poisoning, and among all infectious diseases it ranks 1st.

Etiology. The causative agents of pneumonia can be almost all known infectious agents: more often - gram-positive and gram-negative bacteria, less often - mycoplasma, chlamydia, legionella, viruses, etc. Associations of two or more microorganisms are possible. The etiological structure of pneumonia depends on the conditions under which the disease occurs.

According to the International Consensus and Standards (protocols) for the diagnosis and treatment of patients with nonspecific lung diseases, the Ministry of Health of the Russian Federation (1998), based on epidemiological and clinical-pathogenetic features, all pneumonia is divided into 4 groups:

I. Community-acquired (out-of-hospital) pneumonia that developed in community-acquired conditions, including “atypical” pneumonia caused by “atypical” intracellular microorganisms.

II. Intrahospital (hospital or nosocomial) pneumonia that developed within 48–72 hours or more after the patient was admitted to the hospital for another disease.

III. Pneumonia in immunodeficiency states ( congenital immunodeficiency , HIV infection, drug (iatrogenic) immunosuppression).

IV. Aspiration pneumonia.

Each group of pneumonia is characterized by its own spectrum of infectious pathogens, which makes it possible to more specifically prescribe antibacterial therapy at the initial stage of treatment before verification of the pathogens.

I. When community-acquired pneumonia the most common pathogens are: pneumococcus (40–60%), mycoplasma (15–20%), Haemophilus influenzae (15–25%), Staphylococcus aureus (3–5%), Klebsiella pneumoniae (3–7%), Legionella ( 2–10%), respiratory viruses (2–15%), chlamydia.

II. For nosocomial pneumonia The most common gram-negative infectious agents are: Klebsiella pneumoniae (Friedlander's bacillus), Pseudomonas aeruginosa, Escherichia coli, Proteus, as well as Staphylococcus aureus and anaerobes. They highlight.

III. Pathogens of pneumonia in patients with immunodeficiency conditions in addition to the usual gram-positive and gram-negative bacteria, there are cytomegaloviruses, which are considered markers of HIV infection, pneumocystis, pathogenic fungi, and atypical mycobacteria.

IV. Aspiration pneumonia most often caused by associations of Staphylococcus aureus and gram-negative bacteria with anaerobic microorganisms, always present in the oral cavity and nasopharynx.

During periods of influenza epidemics, the etiological role of viral-bacterial associations, as well as opportunistic microorganisms, increases. By damaging the mucous membranes of the respiratory tract, respiratory viruses (influenza viruses, adenoviruses, respiratory syncytial viruses, etc.) open the “gate” for bacterial flora, most often staphylococci.

Determining the etiology of pneumonia is difficult. At the initial stage, the etiological diagnosis is empirical (presumptive) and is made taking into account clinical and epidemiological data. Thus, with the development of nosocomial pneumonia in a patient in a purulent surgical department, staphylococcal etiology is most likely. Community-acquired lobar pneumonia is most often pneumococcal. A group outbreak is characteristic of mycoplasma pneumonia. In order to identify pathogens, the patient’s sputum and bronchial washings are examined. In the diagnosis of mycoplasma and viral pneumonia, the complement fixation reaction (CFR) is used with the patient’s blood serum and antigens of viruses or mycoplasma. Even with a well-equipped microbiological laboratory, the etiology of pneumonia can only be determined in 50-60% of cases.

Pathogenesis. Risk factors pneumonia are hypothermia, childhood and old age, smoking, stress and overwork, smoking and alcohol abuse, exposure to adverse environmental and occupational factors on the respiratory system, influenza epidemics, chronic bronchitis, congestion in the pulmonary circulation, immunodeficiency states, contact with birds and rodents, staying in air-conditioned rooms, prolonged bed rest, bronchoscopic examinations, mechanical ventilation, tracheostomy, anesthesia, septic conditions, etc.

In the pathogenesis of pneumonia, the pathogenic properties of infectious microorganisms and the patient’s defense mechanisms interact.

The lower respiratory tract is normally sterile thanks to the system of local bronchopulmonary protection: mucociliary clearance (mucociliary lifting cleansing of the bronchi), production in the bronchi and alveoli of humoral protective factors (Ig A, lysozyme, complement, interferons, fibronectin), alveolar surfactant and phagocytic activity of alveolar macrophages, the protective function of broncho-associated lymphoid tissue.

Pneumonia pathogens enter the respiratory tracts of the lungs from the environment most often bronchogenic through inhaled air or aspiration from the oral cavity and nasopharynx. Hematogenous And lymphogenous routes of infection into the lungs are observed in sepsis, general infectious diseases, thromboembolism, and chest injuries. Inflammation of the lung tissue can develop without exposure to external infectious agents - with the activation of opportunistic microflora located in the patient’s respiratory tract, which occurs when the general reactivity of the body decreases.

When infectious microorganisms enter the respiratory tract, they adhere to the surface of the bronchial and alveolar epithelium, leading to damage to cell membranes and colonization of pathogens in epithelial cells. This is facilitated by previous damage to the epithelium by viruses, chemicals, weakening of general and local protective mechanisms as a result of exposure to infectious and other unfavorable factors of the external and internal environment.

Further development of the inflammatory process is associated with the production of endo- or exotoxins by infectious agents, the release of humoral and cellular inflammatory mediators in the process of damage to lung tissue by the influence of infectious microorganisms, neutrophils and other cellular elements. Humoral mediators of inflammation include complement derivatives, kinins (bradykinin). Cellular mediators of inflammation are represented by histamine, arachidonic acid metabolites (prostaglandins, thromboxane), cytokines (interleukins, interferons, tumor necrosis factor), lysosomal enzymes, reactive oxygen metabolites, neuropeptides, etc.

Pneumococci, Haemophilus influenzae, Klebsiella pneumoniae produce endotoxins (hemolysins, hyaluronidase, etc.), which sharply increase vascular permeability and contribute to pronounced edema of the lung tissue.

Pneumococcal(lobar or lobar) pneumonia begins in the form of a small focus of inflammation in the lung parenchyma, which, due to the formation of excess edematous fluid, spreads “like an oil slick” from alveoli to alveoli through Cohn’s pores until it covers the entire lobe or several lobes. With early treatment, the inflammatory process can be limited to a segment of the lung. Pneumococci are located on the periphery of the inflammatory focus, and in its center a germ-free zone of fibrinous exudate is formed. The term “lobar pneumonia,” common in Russian pulmonology, comes from the word “croup,” which means a certain type of fibrinous inflammation.

Friedlander's pneumonia, caused by Klebsiella and similar in development to pneumococcal pneumonia, is characterized by thrombosis of small vessels with the formation of necrosis of the lung tissue.

Streptococci, staphylococci and Pseudomonas aeruginosa allocate exotoxins, destroying lung tissue and forming foci of necrosis. Microorganisms are located in the center of the inflammatory-necrotic focus, and inflammatory edema is observed along its periphery.

Mycoplasma, chlamydia and legionella are characterized by long-term persistence and replication within the cells of the macroorganism, which determines their high resistance to antibacterial drugs.

In the pathogenesis of pneumonia, sensitization of the body to infectious microorganisms is of particular importance, the severity of which determines the characteristics of the clinical course of the disease. The body's response in the form of the formation of antimicrobial antibodies and immune complexes (antigen-antibody-complement) contributes to the destruction of pathogens, but at the same time leads to the development of immunoinflammatory processes in the lung tissue. When the pulmonary parenchyma is damaged by infectious microorganisms, autoallergic reactions of the cellular type may develop, contributing to the protracted course of the disease.

A hyperergic inflammatory reaction in the alveolar zone is especially characteristic of pneumococcal (lobar) pneumonia, which is associated with sensitization of the body to pneumococcus, which is present in the normal microflora of the upper respiratory tract in 40–50% of healthy individuals. Focal pneumonia often manifests itself as a normo- or hypergic inflammatory reaction.

Taking into account pathogenetic factors, pneumonia is divided into primary and secondary. Primary pneumonia develops as an acute infectious-inflammatory process in a previously healthy person, secondary pneumonia occurs against the background of chronic respiratory diseases or pathologies of other organs and systems.

According to the mechanism of development, secondary pneumonia is often bronchopneumonia - local bronchitis develops first, and then the inflammatory process spreads to the alveolar tissue.

Pathological picture most typical for pneumococcal (lobar) pneumonia, which has a cyclic course. Highlight high tide stage(from 12 hours to 3 days), which is characterized by hyperemia and inflammatory edema of the lung tissue. In the next stage, lesions appear red and gray hepatization of lung tissue(from 3 to 6 days) as a result of diapedesis of erythrocytes, leukocytes and effusion of plasma proteins, primarily fibrinogen, into the alveoli. Stage permissions(duration varies individually) is characterized by gradual dissolution of fibrin, filling of the alveoli with macrophages and restoration of airiness in the affected parts of the lungs. Against the background of the separation of purulent sputum through the respiratory tract (in the stage of resolution), local bronchitis is usually associated with pneumonia. Pneumococcal pneumonia is characterized by fibrinous pleurisy.

With focal pneumonia, a mosaic pathological picture is observed within one or several segments. The inflammatory process involves lobules or groups of lobules, alternating with areas of atelectasis and emphysema or normal lung tissue. The exudate is most often serous, but can be purulent or hemorrhagic. Focal confluent pneumonia often develops. The pleura is usually not affected.

Classification. When making a diagnosis, be sure to indicate epidemiological group of pneumonia(according to the International Consensus and Standards (protocols) for the diagnosis and treatment of patients with nonspecific lung diseases, Ministry of Health of the Russian Federation, 1998), clarified etiology(according to ICD-10 revision) and basic clinical and morphological signs taking into account the widespread classification of pneumonia in Russia, developed by N.S. Molchanov (1962) in a later modification by E.V. Gembitsky (1983).

CLINICAL CLASSIFICATION OF PNEUMONIA

(N.S.Molchanov, 1965; E.V.Gembitsky, 1983)

By etiology:

Bacterial (indicating the pathogen)

Viral (indicating the pathogen)

Mycoplasma

Rickettsial (pulmonary form of Q fever)

Ornithosis

Fungal

Mixed (viral-bacterial)

Unknown etiology

By pathogenesis:

Primary

Secondary (stagnant-hypostatic, infarction-pneumonia, postoperative, burn, septic-metastatic, etc.)

With the flow:

Protracted (more than 4 weeks)

By localization:

One- and two-sided

According to clinical and morphological characteristics:

Parenchymatous:

a) lobar, segmental (lobar)

b) focal (bronchopneumonia)

Interstitial

By severity:

Mild degree

According to the state of external respiration function:

No functional impairment

Respiratory failure I, II, III degrees.

Sample formulation of the diagnosis of pneumonia:

Basic: Community-acquired pneumococcal pneumonia of the lower lobe of the right lung, moderate severity

Complication: DN – II Art. Exudative pleurisy on the right

Many authors dispute the validity of the independent diagnosis of “interstitial pneumonia,” since reactive changes in the interstitial tissue are observed in many pulmonary and extrapulmonary diseases. This form of pneumonia is diagnosed more often with a viral or psittacosis infection.

Clinical picture. Clinical manifestations of pneumonia depend on epidemiological conditions, the clinical and morphological form of the disease, the type of pathogen and the state of the macroorganism.

In all cases it is possible to distinguish main clinical syndromes:

1) intoxicating(weakness, weakness, headaches and muscle pain, pallor);

2) general inflammatory changes(chills, increased body temperature, neutrophilic leukocytosis with a shift in the leukocyte formula to the left, increased ESR, levels of seromucoids, fibrinogen, appearance of C-reactive protein);

3) inflammatory changes in lung tissue(cough with sputum, chest pain, increased vocal tremors, dullness of percussion sound, changes in breathing patterns, the appearance of crepitus or moist fine rales, radiological signs of infiltration of the lung tissue);

4) involvement of other organs and systems(cardiovascular system, nervous, digestive, kidney, blood system).

The most typical clinical picture is community-acquired pneumococcal (lobar) pneumonia, which develops more often in young and middle-aged men.

It begins acutely against the background of complete health, usually after hypothermia. The patient develops severe chills, severe weakness, headache and muscle pain, and an increase in body temperature to 39-40°. Shortness of breath is a concern with light exertion or even at rest. There is pain in the chest on the affected side, which intensifies with deep breathing or coughing and is associated with the involvement of the pleura in the pathological process. With lower lobe localization of pneumonia due to damage to the diaphragmatic pleura, pain radiates to the abdominal wall, simulating the picture of an acute abdomen. The cough appears at first dry, and from the 2-3rd day - with the discharge of a small amount of viscous sputum streaked with blood - “rusty”. Subsequently, the sputum becomes purulent or mucopurulent in nature.

When examining the patient, pale skin, cyanosis of the nasolabial triangle, and herpetic rashes on the lips and wings of the nose (due to an exacerbation of persistent herpetic infection) are noted. In severe cases of the disease, disturbances of consciousness and delirium are possible. The body position is often forced - lying on the affected side - to reduce respiratory excursions of the affected lung. Breathing is shallow, increased to 30-40 per minute. Participation in breathing of the wings of the nose and other auxiliary respiratory muscles, and lag of the diseased half of the chest are observed. Palpation of the intercostal spaces in the area of the affected lobe of the lung is painful. Voice tremors increased. Percussion of the lungs reveals shortening and then a pronounced dullness of the percussion sound.

During auscultation in the initial stage of pneumonia, somewhat weakened vesicular breathing is heard, which, with inflammatory compaction of the lung tissue (on the 2-3rd day of illness), is replaced by bronchial breathing. From the first days of the disease (in the flushing stage) it is heard crepitus– characteristic crackling sound when swollen alveoli dissolve at the height of inspiration (crepitatio indux). It is a pathognomonic sign of lobar pneumonia. At the peak of pulmonary inflammation, when the alveoli are filled with inflammatory exudate (red and gray liver stage), crepitus disappears. Pleural friction rub is often detected. With the discharge of sputum, scattered dry and sonorous fine-bubbly, moist rales appear, caused by local bronchitis.

From the cardiovascular system, tachycardia and hypotension are usually detected, up to collapse.

When adequate treatment of pneumonia is started in a timely manner, the patient’s body temperature quickly decreases and signs of intoxication decrease. As the source of inflammation resolves, percussion dullness is limited, breathing becomes vesicular and harsh. The amount of moist rales decreases, and crepitatio redux reappears. Uncomplicated lobar pneumonia resolves by the end of the 2-3rd week.

Community-acquired focal pneumococcal pneumonia is diagnosed in 80-85% of all cases of pneumonia. In terms of pathogenesis, it is usually secondary - it develops against the background of an acute respiratory infection, exacerbation of chronic bronchitis or other somatic pathology. It is more common in children and the elderly, weakened by frequent colds or other factors predisposing to pneumonia. The clinical picture of the disease is variable due to the variety of its pathogens (bacteria, including pneumococci, mycoplasma pneumoniae, viruses, rickettsia). The cyclical nature of the disease, characteristic of lobar pneumonia, is absent. The severity of the condition and physical findings depend on the extent of the process.

The disease can begin acutely, after hypothermia, with an increase in body temperature to 38-39 o, or gradually against the background of prodromal phenomena. In weakened patients, the body temperature may be low-grade. A dry cough or with mucopurulent sputum, shortness of breath, general weakness, sweating, and headache appear. If pneumonia is associated with an exacerbation of chronic bronchitis, an increase in “bronchitis” cough or an increase in the amount of mucopurulent sputum discharge is noted. Chest pain with focal pneumonia is usually absent, since the inflammatory process does not involve the pleura. Sweating is common with little physical activity.

Objective data are more scarce than for lobar pneumonia. On examination, pallor of the skin is observed, and with concomitant chronic diseases of the respiratory system or cardiovascular system - cyanosis, increased breathing. There is some lag in the diseased half of the chest when breathing. Above the areas of infiltration, an increase in vocal tremors and a shortening of the percussion sound are determined. On auscultation, against the background of hard vesicular breathing, dry and sonorous fine-bubbly, moist rales are heard. Large-focal (confluent) infiltration of lung tissue, according to physical data, resembles lobar pneumonia, but crepitus is not typical for focal pneumonia. With small inflammatory foci, a “mosaic” picture is possible - alternating areas of dullness of percussion sound with areas of normal or boxy, hard breathing with weakened breathing.

Pneumococcal pneumonia, both lobar and focal, is not characterized by destruction of lung tissue, since pneumococci do not produce exotoxins. This also explains the almost complete restoration of the structure of the lung tissue and the function of external respiration.

Community-acquired pneumonia caused by other infectious agents has its own clinical characteristics.

Mycoplasma pneumonia is caused by an “atypical” intracellular pathogen, devoid of a cell membrane and approaching the size of viruses. It most often affects young people and is characterized by epidemic outbreaks in organized groups, reaching a frequency of 30%. It usually begins with a picture of an acute respiratory infection, then a painful, often paroxysmal cough appears with scanty mucopurulent sputum, and a disturbing feeling of “soreness” in the throat. Physical data are scarce due to the predominantly interstitial localization of inflammation. Against the background of hard breathing, a few dry rales are heard in the lower parts of the lungs. It is possible that focal infiltration of the lung tissue may occur with the appearance of dullness of percussion sound and moist fine rales over the affected area. Characteristic is the dissociation of clinical manifestations of the disease (severe intoxication, prolonged low-grade fever, heavy sweats), X-ray picture (only increased pulmonary pattern and interstitial changes) and laboratory data (absence of leukocytosis and neutrophilic shift). Extrapulmonary manifestations of mycoplasma infection are often detected - myalgia, arthralgia, myocarditis. The resolution of mycoplasma pneumonia is delayed, and the asthenic syndrome persists for a long time.

Rickettsial pneumonia (Q fever) has an acute onset, with a temperature of 39-40 o and repeated chills for 10-12 days. Severe intoxication, muscle pain, especially lumbar and calf pain, insomnia, and dyspeptic symptoms are observed. Worried about a cough with a small amount of sputum, chest pain. The cervical lymph nodes are often enlarged. Characterized by slight jaundice and hepatolienal syndrome. Physical data are scarce. Diagnosis is helped by a positive epidemiological history (contact with farm animals) and the complement fixation reaction with Qui-rickettsia antigens.

Legionella pneumonia(legionnaires' disease ) usually develops in epidemic individuals , staying in rooms with air conditioning, in the water systems of which favorable conditions are created for the life of the virulent gram-negative bacillus - Legionella. It is characterized by the fusion of foci of inflammation and high mortality of patients (15-30%). The clinical picture of the disease is characterized by prolonged fever (15 days or more), frequent extrapulmonary lesions, prolonged course, leukocytosis in combination with lymphopenia.

Ornithosis pneumonia caused by chlamydia psittacosis due to contact with infected birds. More often it occurs as interstitial pneumonia with poor physical data. The clinical picture is dominated by general toxic signs of infection - headache and muscle pain, fever, vomiting, sleep disturbances. Characterized by bradycardia, hypotension, dry tongue, flatulence, enlarged liver and spleen. The diagnosis is confirmed by an epidemiological history (contact with birds) and a skin allergy test.

Pneumonia due to respiratory viral infections develop under the influence of viral-bacterial associations. They are more often diagnosed during epidemics of viral infections. The main role of respiratory viruses is to damage the bronchial epithelium and suppress general and local immunity, which leads to the activation of opportunistic microorganisms and the penetration of infection (most often pneumococcus and Haemophilus influenzae) into the respiratory sections of the lungs. The diagnosis of viral-bacterial pneumonia is usually based on an assessment of the epidemiological conditions of the disease. Clinically, viral-bacterial pneumonia occurs as focal or focal-confluent with a noticeable reaction of the interstitial tissue of the lungs. With various viral infections, pneumonia has its own clinical characteristics. To detect and identify viruses, serological methods, enzyme-linked immunosorbent assay and polymerase chain reaction (PCR) are used.

Pneumonia due to influenza infection usually develop in the first three days from the onset of the disease and are characterized by severe intoxication and symptoms of hemorrhagic bronchitis. A two-wave fever is characteristic - the first wave reflects a viral infection, and the second - a bacterial infection.

Pneumonia due to adenovirus infection accompanied by symptoms typical of adenovirus infection - conjunctivitis, pharyngitis, enlarged peripheral lymph nodes.

Pneumonia due to respiratory syncytial virus infection is characterized by the development of bronchiolitis and obstructive bronchitis with intoxication and severe broncho-obstructive syndrome.

Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa in most cases are the causes of nosocomial pneumonia.

Staphylococcal pneumonia characterized by a severe course and rapid development of purulent destructive complications - lung abscesses, pleural empyema. Often develops after influenza with a decrease in general and local bronchopulmonary protective mechanisms. It begins acutely, with chills and high fever, cough with purulent sputum, shortness of breath, chest pain, which resembles lobar pneumonia. The severity of the condition does not always correspond to physical data. Characterized by a clear segmentation of the lesion involving several segments of the lungs and a tendency to rapid abscess formation with the formation of multiple thin-walled cavities. When abscesses open into the pleural cavity, pyopneumothorax occurs.

Friedlander's pneumonia Caused by Gram-negative endotoxin-producing Friedlander's bacillus or Klebsiella pneumoniae. It often affects people who abuse alcohol, the elderly, people with diabetes, and injection drug addicts. Men get sick 5-7 times more often. An acute onset with severe intoxication, an increase in body temperature to 38-39 o, the appearance of chest pain when breathing, and a painful cough resembles severe pneumococcal pneumonia. From the first day, profuse, viscous, bloody sputum appears with the smell of burnt meat. Due to the large amount of exudate clogging the lumen of the alveoli and bronchi, a small amount of wheezing is heard. The appearance of early multiple destruction of lung tissue (in the first two days) is convincing evidence in favor of pneumonia caused by Klebsiella. Frequent involvement of the upper lobe of the lung may cause an erroneous diagnosis of tuberculosis. Friedlander's pneumonia is characterized by a protracted course with the outcome in pneumofibrosis of the affected lobe.

Pneumonia caused by Pseudomonas aeruginosa stick usually develops in the postoperative period, in patients on mechanical ventilation (ventilator-associated pneumonia). It begins acutely with high fever with chills, severe intoxication, and respiratory failure. Physical examination reveals signs of focal lung damage. Pleural complications and abscess formation are typical. The disease is characterized by a particularly severe course and high mortality, reaching 50–70% in elderly weakened patients.

Laboratory and instrumental diagnosis of pneumonia:

General blood analysis reveals neutrophilic leukocytosis with a shift in the leukocyte formula to the left, an increase in ESR. The degree of these changes determines the prevalence and severity of the process: with lobar pneumonia, leukocytosis reaches 20-30 thousand with a shift of the leukocyte formula to the left to juvenile forms. Toxic granularity of neutrophils (++++), aneosinophilia are detected. With focal bacterial pneumonia, the changes are less pronounced - leukocytosis in the range of 10-12 thousand, a shift to the left up to 10% of stabs, toxic granularity of neutrophils (++). Viral pneumonia is characterized by leukopenia with a low ESR. With mycoplasma and psittacosis infections, a normal leukocyte count or leukopenia can be combined with a high ESR.

Blood chemistry reveals an increase in α 2 - globulins, sialic acids, seromucoids, and the appearance of C-reactive protein. In severe pneumonia, signs of blood hypercoagulation are revealed - the level of fibrinogen increases 2-3 times, the platelet count decreases. When the inflammatory process resolves, the fibrinolytic activity of the blood increases sharply.

Sputum analysis detects leukocytes, erythrocytes (with lobar, Friedlander, post-influenza pneumonia), elastic fibers (with abscess formation). During its bacteriological examination, the type of pathogen and its sensitivity to antibiotics are determined.

X-ray of the lungs is the most informative diagnostic method. With lobar pneumonia, an intense, uniform darkening is determined within a lobe or segment, which completely resolves under the influence of treatment within 2-3 weeks. Lobar lesions (usually the upper lobe) are characteristic of Friedlander pneumonia, and segmental lesions are characteristic of staphylococcal pneumonia. The last two variants of pneumonia are characterized by the rapid development of multiple destruction of lung tissue.

With focal pneumonia, foci of infiltration of various sizes and intensity are detected, most often in the lower parts of the lungs. With adequate treatment, pulmonary infiltrates resolve within 7-10 days. Viral, rickettsial and mycoplasma pneumonias are characterized by a severe pulmonary pattern due to the interstitial component of inflammation.

Spirography detects disturbances in the function of external respiration of a restrictive type, which is manifested by a decrease in minute volume of respiration (MVR), vital capacity (VC) and maximum pulmonary ventilation (MVL). In case of focal pneumonia that has developed against the background of chronic obstructive bronchitis, disturbances in the function of external respiration of the obstructive type are detected, as evidenced by a decrease in the forced expiratory volume in 1 second (FEV 1) and the Votchal-Tiffen test (FEV 1 / VC).

Serological blood tests help in the diagnosis of mycoplasma, rickettsial, legionellosis, ornithosis and viral pneumonia. The titer of antibodies to the pathogen is determined by the method of paired sera (an increase in titer of 4 times or more is reliable).

Sometimes, with severe or atypical pneumonia, it becomes necessary to use more complex examination methods, such as bronchoscopy with biopsy, computed tomography of the lungs, examination of pleural fluid, ultrasound of the heart and abdominal organs.

Summarizing the above data, we can determine “gold” diagnostic standard(A.G. Chuchalin, 2000) for early diagnosis of pneumonia already at the outpatient stage:

1. Acute onset of the disease with fever and intoxication.

2. The appearance of a dry cough or with phlegm, chest pain.

3. Dullness of percussion sound and the appearance of auscultatory phenomena of pneumonia (crepitus, fine moist rales).

4. Leukocytosis or, less commonly, leukopenia with a shift to the left.

5. Detection of infiltrate in the lung during x-ray examination.

By severity all pneumonias are conditionally divided into three groups:

1. Pneumonia with a light current, not requiring hospitalization. This group accounts for up to 80% of all pneumonias. Patients can be treated on an outpatient basis under the supervision of a doctor or in a day hospital at a clinic. Mortality in this group does not exceed 1-5%.

2. Moderate pneumonia, requiring hospitalization patients to the hospital. This group includes about 20% of all pneumonias, which usually occur against the background of chronic diseases of internal organs and have pronounced clinical symptoms. The mortality rate of hospitalized patients reaches 12%.

Pneumonia is an acute inflammatory disease of the respiratory parts of the lungs, predominantly of bacterial etiology, characterized by intra-alveolar exudation.

The occurrence of the disease is caused by the penetration of saprophytic microbes from the oropharynx into the lower respiratory tract - alveoli and bronchioles. Less commonly, pathogens spread through lymphatic capillaries or blood vessels from foci of infection in neighboring organs. The causative agents of pneumonia are most often pneumococci (lobar pneumonia), staphylococci, streptococci and other microbes.

The clinical (external) manifestations of the disease are influenced by many factors:

properties of the pathogen microbe;

the nature of the course and stage of the disease;

structural (morphological) basis of the disease;

prevalence of the process in the lungs;

the presence of complications - pulmonary suppuration, pleurisy or empyema.

Modern classification of pneumonia

Classification according to ICD-10 (by forms and timing of occurrence):

Out-of-hospital - occurs at home or in the first 48 hours of stay in a medical institution. The course is relatively favorable, the mortality rate is 10-12%.

Hospital (nosocomial) - occurs after 48 hours of the patient’s stay in the hospital or if the patient has been treated in any medical institution for 2 or more days over the previous 3 months. In modern protocols, the World Health Organization (WHO) includes in this category patients with ventilator-associated pneumonia (who are on mechanical ventilation for a long time), as well as patients with pneumonia who are kept in nursing homes. It is characterized by a high degree of severity and mortality up to 40%.

Aspiration pneumonia - occurs when a large amount of oropharyngeal contents is swallowed by unconscious patients with impaired swallowing and a weakened cough reflex (alcohol intoxication, epilepsy, traumatic brain injury, ischemic and hemorrhagic strokes, etc.). Aspiration of gastric contents may cause a chemical burn of the mucous membrane of the respiratory tract with hydrochloric acid. This condition is called chemical pneumonitis.

Pneumonia developing against the background of immunodeficiencies, both primary (thymic aplasia, Bruton's syndrome) and secondary (HIV infection, oncohematological diseases).

Community-acquired pneumonia (domestic, home, outpatient), that is, acquired outside a medical institution, usually develops when the protective mechanisms of the respiratory system are impaired. Pneumonia often complicates the course of a respiratory viral infection, such as influenza. The main causative agent of community-acquired pneumonia is pneumococcus. It can also be caused by streptococci or Haemophilus influenzae.

Depending on the extent of organ damage:

lobar pneumonia (pleuropneumonia) - affecting the lobe of the lung;

focal pneumonia (bronchopneumonia) with damage to the group of alveoli adjacent to the inflamed bronchus;

Interstitial pneumonia is inflammation of lung tissue along the bronchi and pulmonary blood vessels.

Lobar pneumonia is only one of the forms of pneumococcal pneumonia, and does not occur with pneumonia caused by other pathogenic microbes.

Classification by pathogen:

Bacterial - the main pathogens are Streptococcus pneumonia, Staphylococcus aureus, Mycoplasmapneumonia, Haemophilus influenza, Chlamydiapneumonia.

Viral - often caused by influenza viruses, parainfluenza, rhinoviruses, adenoviruses, respiratory syncytial virus. In more rare cases, these may be measles, rubella, whooping cough viruses, cytomegalovirus infection, and Epstein-Barr virus.

Fungal - the main representatives in this category are Candida albicans, fungi of the genus Aspergillus, Pneumocystisjiroveci.

Pneumonia caused by protozoa.

Pneumonia caused by helminths.

Mixed - this diagnosis occurs most often with a bacterial-viral association.

Forms of pneumonia by severity:

extremely heavy.

The inflammatory process occurs:

one-sided;

bilateral.

Etiology

Lobar pneumonia most often develops against the background of overwork, hypothermia, lack of vitamins and minerals, and disruption of the immune system. The causes of this lung disease include the following factors:

1. Diseases suffered the day before (colds or infections).
2. Intoxication of the body.
3. Harmful working conditions.
4. Living in premises with an unfavorable microclimate and severe dampness.
5. Penetration of pathogens of lobar pneumonia (streptococci, pneumococci, staphylococci, Friendler's bacillus) into the patient's body, which, entering the pulmonary parenchyma, provoke the development of an acute inflammatory process and the appearance of the first symptoms of the disease.

Risk factors for developing pneumonia, as defined by WHO in 1995, include:

old age - people over 60 years of age (due to suppression of the cough reflex, the reflex responsible for spasm of the glottis);

the period of newbornhood and infancy (the reason is the incomplete development of the immune system);

conditions accompanied by loss of consciousness (epilepsy, traumatic brain injury, anesthetized sleep, suicide attempts with sleeping pills or drugs, alcohol intoxication);

respiratory diseases (chronic bronchitis, emphysema, acute respiratory distress syndrome), smoking;

concomitant diseases that reduce the activity of the immune system (oncological diseases, systemic connective tissue diseases, HIV infection, etc.);

negative social and living conditions, malnutrition;

keeping the patient in a lying position for a long time.

The main causes of the disease according to WHO

Risk factors for developing pneumonia, as defined by WHO in 1995, include:

old age - people over 60 years of age (due to suppression of the cough reflex, the reflex responsible for spasm of the glottis);
the period of newbornhood and infancy (the reason is the incomplete development of the immune system);
conditions accompanied by loss of consciousness (epilepsy, traumatic brain injury, anesthetized sleep, suicide attempts with sleeping pills or drugs, alcohol intoxication);
respiratory diseases (chronic bronchitis, emphysema, acute respiratory distress syndrome), smoking;
concomitant diseases that reduce the activity of the immune system (oncological diseases, systemic connective tissue diseases, HIV infection, etc.);
negative social and living conditions, malnutrition;
keeping the patient in a lying position for a long time.

Classification according to ICD-10 (by forms and timing of occurrence)

Out-of-hospital - occurs at home or in the first 48 hours of stay in a medical institution. The course is relatively favorable, the mortality rate is 10-12%.
Hospital (nosocomial) – occurs after 48 hours of the patient’s stay in the hospital or if the patient has been treated in any medical institution for 2 or more days over the previous 3 months. In modern protocols, the World Health Organization (WHO) includes in this category patients with ventilator-associated pneumonia (who are on mechanical ventilation for a long time), as well as patients with pneumonia who are kept in nursing homes. It is characterized by a high degree of severity and mortality up to 40%.
Aspiration pneumonia - occurs when a large amount of oropharyngeal contents is swallowed by unconscious patients with impaired swallowing and a weakened cough reflex (alcohol intoxication, epilepsy, traumatic brain injury, ischemic and hemorrhagic strokes, etc.). Aspiration of gastric contents may cause a chemical burn of the mucous membrane of the respiratory tract with hydrochloric acid. This condition is called chemical pneumonitis.
Pneumonia developing against the background of immunodeficiencies, both primary (thymic aplasia, Bruton's syndrome) and secondary (HIV infection, oncohematological diseases).

Varieties by pathogen, severity and localization

Classification by pathogen:

Bacterial - the main pathogens are Streptococcus pneumonia, Staphylococcus aureus, Mycoplasmapneumonia, Haemophilus influenza, Chlamydiapneumonia.
Viral - often caused by influenza viruses, parainfluenza, rhinoviruses, adenoviruses, respiratory syncytial virus. In more rare cases, these may be measles, rubella, whooping cough viruses, cytomegalovirus infection, and Epstein-Barr virus.
Fungal - the main representatives in this category are Candida albicans, fungi of the genus Aspergillus, Pneumocystisjiroveci.
Pneumonia caused by protozoa.
Pneumonia caused by helminths.
Mixed - this diagnosis occurs most often with a bacterial-viral association.

Forms of pneumonia by severity:

light;
average;
heavy;
extremely heavy.

Types of pneumonia by localization:

Focal – within the acinus and lobule.
Segmental, polysegmental - within one or several segments.
Lobar (outdated diagnosis: lobar pneumonia) – within one lobe.
Total, subtotal - can cover the entire lung.

The inflammatory process occurs:

one-sided;
bilateral.

From birth to 3 weeks - the etiological agent of pneumonia (more often in premature infants) are group B streptococci, gram-negative bacilli, cytomegalovirus infection, Listeria monocytogenes.
From 3 weeks to 3 months - in most cases, children are affected by a viral infection (respiratory syncytial virus, influenza viruses, parainfluenza, metapneumovirus), Streptococcus pneumoniae, Staphylococcus aureus, Bordetellapertussis, Chlamydiatrachomatis (nasal infection).
From 4 months to 4 years - at this age, the susceptibility of children increases to group A streptococci, Streptococcus pneumoniea, viral infections (parainfluenza viruses, influenza viruses, adenoviruses, rhinoviruses, respiratory syncytial viruses, metapneumoviruses), Mycoplasmapneumoniae (in older children).
From 5 to 15 years - at school age, pneumonia in children is most often caused by Streptococcus pneumoniae, Mycoplasmapneumoniae, Chlamydiapneumoniae.

Clinical categories of patients with community-acquired pneumonia according to ICD-10

Forms of nosocomial inflammation according to WHO

Early - occur during the first 4-5 days from the moment of admission to the hospital, have a relatively favorable diagnosis, microorganisms are generally sensitive to antibiotic therapy.
Late - appear after 6 days of stay in a medical institution, the diagnosis in most cases is questionable or unfavorable, the pathogens are multi-resistant to antibiotics.

Criteria for severe disease

the appearance on the radiograph of “fresh” focal infiltrative changes in the lungs;
temperature over 38°C;
bronchial hypersecretion;
Pa O2/Fi O2 ≤ 240;
cough, tachypnea, locally auscultated crepitations, moist rales, bronchial breathing;
leukopenia or leukocytosis, band shift (more than 10% of young forms of neutrophils);
sputum microscopy reveals more than 25 polymorphonuclear leukocytes in the field of view.