High level of lymphocytes in the child’s blood. High lymphocytes in the blood of a child: a manifestation of pathology

The materials are published for informational purposes only and are not a prescription for treatment! We recommend that you consult a hematologist at your medical institution!

The composition of a child's blood differs from that of an adult and depends on the specific age. To identify disorders in the body, it is important to know how to recognize the increase and decrease in lymphocytes, determine the cause and immediately take appropriate measures.

Normally, a child’s lymphocytes are elevated when compared with adult levels. However, it is important to monitor the range of deviations so as not to miss the development of serious diseases. Let's look at the most common situations.

general characteristics

First, let's take a closer look at what lymphocytes are and what their functions are in the body. They are part of the white group blood cells. Lymphocytes are responsible for maintaining immune defense. The norm for a child differs due to the fragile immune system.

Functions of lymphocytes

There are three main categories of these cells: T, B and NK. Each has its own classification and is responsible for the implementation of specific tasks. The main functions are:

• production of antibodies and related enzymes;
• destruction of foreign cells;
• suppression of autoimmune reactions;
• elimination of own mutant cells;
• creation of sustainable immunity.

Important: when foreign agents enter the body, activated killer cells break down their protein and prevent the development of the disease.

There are also atypical cells. They are distinguished by their shape and curved core. They are capable of performing the same functions, but most often an increase in their number is associated with pathological processes in organism. If broad plasma lymphocytes are added, there is a risk of developing mononucleosis.

Since lymphocytes are responsible for the formation of immunity, the norm in children will differ depending on age. This is mainly due to the development of protective mechanisms in a fragile body.

If, according to the results of a blood test, lymphocytes are elevated in a child under one year old, in most cases there is no need to worry. This phenomenon is explained by the fact that during this period there is a peak in the production of these cells to create a protective barrier against infections and microbes, as well as the formation of lifelong immunity against certain diseases.

Table: Range normal indicators V general analysis blood for children of different ages

If you are interested in these indicators, they are available on our website and you can familiarize yourself with it.

The norm of lymphocytes in children approximately ranges from 40-70%, while in adults this figure is 20-40%. Cell concentrations peak between 1 and 12 months of age and then begin to decline. By age 12, scores are approaching those of standard adults.

Deviations from the norm

The child's health must be constantly monitored. To do this, it is important not only to monitor his well-being, but also to visit the clinic for control tests.

If the norm of lymphocytes in the child’s blood is not met, it is necessary to carry out additional research to clarify the situation and find out its causes. Sometimes abnormalities in the lymphocytic pattern may be associated with a common cold, but life-threatening pathologies are also possible.

Two types of deviations are possible: an increase and decrease in the level of lymphocytes, both in percentage and in absolute value.

Level up

These are not always the norm in a child’s blood. Depending on the specific age, their concentration is assessed in relative and absolute values. If deviations exceed 15%, they speak of lymphocytosis.

When lymphocytes in a child’s blood are elevated, there are two forms of the problem:

• Relative. The percentage of lymphocytes and other blood cells. This form of lymphocytosis can be provoked by inflammation, accompanied by a purulent process, since in this case white blood cells migrate to the site of infection.
• Absolute. High rates of synthesis of new lymphocytes develop, which increases their total number in the blood.

If in a baby the readings are 3.0-10.0 × 10 9 / l - this is the norm, in older children this may be due to the following reasons:

• viral hepatitis;
• infectious diseases (rubella, chickenpox, measles, whooping cough);
• tuberculosis;
• toxoplasmosis;
• lichen;
• Crohn's disease;
• mononucleosis;
• brucellosis;
• lymphocytic leukemia

It is also worth considering that during any illness the number and activity of lymphocytes increases, which is due to the body’s immune response to the activity of a foreign agent. If the norm is significantly exceeded, unhealthy autoimmune reactions can develop, up to fatal outcome due to self-destruction of the body.

Decrease in indicators

Much more dangerous situation when the child’s lymphocytes are low. This is fraught not only with the presence of serious prerequisites for the development of such a disorder, but also with the inability of the body to fully protect itself from pathogenic agents. If there is a significant deviation below the norm, they speak of lymphocytopenia. The following reasons can provoke it:

• autoimmune pathologies;
• lupus erythematosus;
• lymphogranulomatosis;
• pernicious anemia;
• tuberculosis;
• poisoning of the body and exposure to radiation.

Important: a lack of lymphocytes makes the body unable to fight infections and bacteria, eliminate foci of inflammation and tumor cells.

Relative lymphocytopenia may be associated with an increase in neutrophils. In this case, low test results may be caused by pneumonia or other purulent foci, where most of the lymphocytes rush, reducing their concentration in the peripheral bloodstream.

Treatment of a child

Regardless of which direction the test results have shifted, treatment should be mandatory. The essence of therapy is to identify the causes of the failure and eliminate them. Because we're talking about about fragile children's body, treatment in most cases should be carried out in a hospital under the supervision of a doctor.

April 4, 2017 | Elena Kolchina | No comments yet

Elevated lymphocytes in the blood of a child: causes

Before answering the question of why lymphocytes in the blood are elevated in a child, it is necessary to determine the origin of the data shaped elements, as well as the role they play in the body. This variety cells belong to the category of leukocytes that form immune protection body. In the body of every person there are two fractions of white blood cells, represented by B- and T-lymphocytes.

Why are lymphocytes so important?

The main function of white blood cells is to fight pathogens infectious diseases, as well as with other foreign agents, such as cells of transplanted organs and cancer cells. Protective function lymphocytes is due to their ability to recognize antigens of foreign objects, with the subsequent formation of a specific immune response.

These white blood cells protect human body from the entry of foreign microorganisms into it. The functional identity of these cells depends on their type:

• Killer T cells are responsible for the formation protective forces body;
• T-suppressors inhibit excessive production of antibodies in the body;
• T helper cells have a synthetic function that causes the production of antibodies;
• The so-called B lymphocytes play an equally important role in ensuring the recognition of antigens in the body;
• There are also NK lymphocytes that differentiate and eliminate aggressive cells.

A condition in which the content of lymphocytes is increased is called lymphocytosis.

Norms for the content of lymphocytes in a blood test

If we compare the normal levels of lymphocytes in the blood of an adult and a newborn baby, they are identical. When the baby is 5 days old from birth, percentage These blood cells in the blood test increase to the number of neutrophils, which corresponds to 30-50%. This physiological phenomenon is called crossover leukocyte formula. In this condition, the same number of main groups of leukocytes is observed. By 1 year of life, the quantitative indicators of lymphocytes increase to 65%. Upon reaching 4 years of age, the baby experiences repeated leukocyte crossover. The result of this phenomenon is a decrease in the number of lymphocytes to 30-45%. At the age of 16-18 years this figure reaches age norm adult.

Physiological jumps in lymphocyte counts can only occur twice. Such changes are due to the development of the immune defense of the child’s body. We can talk about pathological lymphocytosis if the content of these blood cells goes beyond the age norm. The following can be noted as normal indicators:

• At 1 year 65%;
• At 5 years 55%;
• At 10 years old 45%.

Causes of increased lymphocytes in a child

The most common cause of an increase in the number of these cells in a child is infectious diseases. What pathologies include:

• Whooping cough;
• Rubella;
• Infectious mononucleosis;
• Flu;
• Viral hepatitis;
• Measles;
• Tuberculosis;
• Smith's disease (acute infectious lymphocytosis).

Important! In progress differential diagnosis it is necessary to take into account the fact that lymphocytosis caused by infectious diseases persists for a certain period of time after recovery. This phenomenon is fully consistent with the normal variant.

In addition, there are reasons similar condition caused by non-infectious effects on the baby’s body. These reasons include:

• Franklin's disease, which is caused by a disruption in the formation of immunoglobulins and the proliferation of lymphoid tissue;
• Chronic and acute lymphocytic leukemia;
• Lymphosarcoma;
• Non-Hodgkin's lymphomas.

For each of listed diseases absolute lymphocytosis is characteristic. A relative increase in white blood cells occurs against the background of such diseases:

• Addison's disease;
• Rheumatoid arthritis;
• Typhoid fever;
• Vitamin deficiency;
• B 12-deficiency anemia;
• Shortage nutrients in the child’s body;
• Congenital hypersensitivity to certain diseases, such as Crohn's vasculitis, ulcerative colitis, serum sickness;
• Thyrotoxicosis;
• Chronic splenomegaly.

Very in rare cases, an increase in the concentration of lymphocytes in a child occurs against the background of routine vaccination, when an increase in the number of antibodies occurs in the child’s body.

The level of white blood cells in the blood is affected by intake hormonal drugs, antibiotics, antiepileptics and others medicines. In the process of analysis quantitative composition blood of the baby, it is recommended to take into account factors such as the absolute concentration of other lymphocytes, age, previous diseases and a list of previously taken medications.

If an increase in the number of white blood cells is accompanied by an increase in body temperature and an acceleration of ESR, then we are talking about the development of a viral infectious process in the baby’s body. This condition requires correction with antiviral medications such as interferons.

Toxic lymphocytosis occurs when substances such as arsenic, tetrachloroethane, carbon disulfide and lead enter the child's body. This condition cannot be considered as separate disease, since it is a natural reaction of the body to other pathological phenomena. Recognize the real reason lymphocytosis is possible only in the process comprehensive examination body.

Symptoms

Most children who encounter this problem do not make any complaints about the deterioration general condition. This fact complicates the process of diagnosing underlying diseases. The reactive form of lymphocytosis is characterized by a synchronous increase in the size of the liver and spleen, as well as regional lymph nodes. IN adolescence this state may be accompanied by infectious diseases oral cavity accompanied by itching, rashes on the mucous membrane, bleeding from the gums and specific coating on the surface of the tongue.

Also, pathological changes affect the palatine tonsils, which become enlarged and hyperemic. In more rare cases infectious process affects the lower and upper Airways, as well as brain matter.

Some children complain of deterioration in general condition, weakness and a feeling of chills. With infectious lymphocytosis, the child’s body temperature can reach 40 degrees. Concomitant manifestations of intoxication of the body are diarrhea, nausea, vomiting, headache And increased sweating. Such children have a reduced or completely absent appetite.

Non-infectious lymphocytosis is characterized by a latent course. Most diseases that cause this phenomenon are diagnosed as a result of a routine examination of the child. In rare cases, there may be an increase in regional lymph nodes, an increase in the size of the liver and spleen, an increase in body temperature within 37.5 degrees, pallor skin, long-lasting bruises, brittle hair and nails, nausea and pain in epigastric region. If one of the symptoms appears, it is recommended to immediately show the baby to a medical specialist and undergo a comprehensive examination.

Treatment

The choice of treatment tactics directly depends on the cause of the increase in the number of white blood cells. If the root of the problem is a viral infection, then the child is prescribed antiviral medications, as well as immunomodulatory drugs.

When cause this phenomenon becomes bacterial infection, then it is advisable to treat it antibacterial drugs wide range actions. Depending on the type of underlying disease, therapeutic tactics has the following form:

1. At functional disorders liver, the baby is recommended to be treated with detoxification drugs, hepatoprotectors and multivitamin complexes. Violation of the functional stability of the liver often occurs against the background of excessive body weight in a child, increased salt intake, as well as exposure to toxic substances on the child’s body;
2. If the provoking factor is acute or chronic inflammatory process, then its relief is carried out by non-steroidal anti-inflammatory drugs, antibacterial drugs and so-called lymphocyte agents;
3. If the cause of lymphocytosis is a malignant pathology, then in this case the child needs specialized assistance oncologist surgeons, chemotherapists and others medical specialists. Treatment malignant neoplasms carried out through surgical intervention, chemotherapy and radiation therapy.

It is important to remember that correction of the quantitative composition of the blood is necessary only for pathological lymphocytosis. Physiological crossovers do not require additional medical intervention.

In the process of diagnosing and treating the underlying disease, parents need to monitor the baby’s condition. Dr. Komarovsky claims that if the child is active, leads a normal lifestyle and his appetite does not suffer, then there is no reason for serious concern. Modern methods laboratory diagnostics have necessary equipment and knowledge to identify the exact cause of this pathological condition.

The term lymphocytes comes from the Latin word lympha - spring water, as well as the Greek kytos - cell or cell. Lymphocytes are a type of white blood cell - leukocyte. They help in the fight against infectious diseases. It is by the concentration of white cells that one can judge the state of the human immune system. So, lymphocytes: the norm in children.

When the body's defense system is attacked dangerous microbes, white blood cells help provide a specific response to counteract the invasion. Lymphocytes also help fight tumors when body cells begin to grow abnormally quickly. But they can also cause tissue rejection in any organ after transplantation, because they consider their cells as foreign.

Lymphocytes are formed in lymphatic tissues, which represent an extensive network - one of the main components of the human immune system. Embryonic stem cells and bone marrow produce B lymphocytes. Moreover, they are the main type of white blood cells contained in a developing child’s body. The normal range for lymphocytes is 15 to 40% of all white blood cells. It is important to note that the range shown may vary depending on the blood testing machine used.

There are three types of lymphocytes:

• B lymphocytes are a type of cell that is produced in lymph nodes and circulates in the blood in an immature form. They make up 10-15% of the total number of blood lymphocytes. B lymphocytes, remembering pathogens, produce antibodies to them and contribute to the emergence of immunity to a certain infection.
• T lymphocytes develop in the thymus, so they are also called thymocytes or killer cells. They make up 80% of all lymphocytes circulating in the blood and are the main group of cells that determines the body's immune response. During an infectious attack on the body, thymocytes begin to multiply rapidly and attack foreign cells.
• From 5 to 10% of total number Lymphocytes make up NK cells or natural killer cells. They destroy infected and cancer cells in the body.

Since lymphocytes are a type of leukocyte, then in decoding clinical analysis blood information about their concentration (LYM) you can see in the composition of the leukocyte formula of leukocytes (under the abbreviation WBC). In addition to information about lymphocytes, it contains data on the concentration of neutrophils (NE), basophils (BA), eosinophils (EO), monocytes (MON), which are also subtypes of white blood cells.

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When interpreting the results of the analysis, it is necessary to take into account that lymphocytes change their concentration depending on age category, this is especially noticeable in childhood.

In babies up to one year old

Studies have shown that B lymphocytes double in absolute value immediately after birth and do not remain stable until two years of age. T-lymphocytes also increase sharply after birth by 1.5 times. And here absolute value natural killer cells, in contrast to B and T lymphocytes, decreases almost threefold during the first 2 months of a child’s life and remains stable after that.

The norm of lymphocytes in the blood of children under one year of age is:

• in newborns in the first day of life - 26-36%, in in absolute terms this amounts to 1.6-7.4 109/l;
• in infants in the first week of life - 36-46% or 2.8-9.0 109/l;
• in the second week - 43-53% or 2.9-9.1 109/l;
• the fourth week corresponds to indicators of 41-71% or 2.8-9.8 109/l;
• in two-month-old infants - 42-72% or 2.9-9.9 109/l;
• in the fourth month of a child’s life - 44-74% or 3.8-10.2 109/l;
• in six months - 46-76% or 4.0-10.5 109/l;
• eight months of age corresponds to 47-77% or 4.0-13.5 109/l;
• upon reaching the first year of life - 46-76% or 4.0-10.5 109/l.

In children aged 2 years

Starting from the age of two, the level of B-lymphocytes in the blood of children gradually begins to decrease - 6.5 times to the adult level. The same thing happens with T-lymphocytes: their concentration decreases three times, gradually reaching adult norm. At two years of age, the norm of lymphocytes in a child’s blood ranges from 44 to 74%, and in absolute numbers - 3.8-10.2 109/l.

For children 3 years and older

What do deviations from the norm indicate?

Lymphocytes are cells of the immune system. Deviations from the norm, when there are a lot of lymphocytes (lymphocytosis) or few (lymphopenia) are considered indicators that not everything is fine in the body. Most common reasons increases in the number of lymphocytes are:

• flu;
• chickenpox;
• whooping cough;
• piggy;
• rubella;
• herpes simplex;
• tuberculosis;
• pneumonia;
• very rarely brucellosis;
• blood transfusion;
• chemical poisoning.

Also, an increase in the concentration of lymphocytes can cause leukemia. This is a type of blood cancer in which the bone marrow is replaced early form white blood cells. There are some specific infections that lead to an excess of lymphocytes:

• Infectious mononucleosis;
• toxoplasmosis;
• infectious hepatitis;
• cytomegalovirus.

There are many reasons that lead to an abnormally low concentration of lymphocytes - about 15%. These include:

• aplastic anemia, when lymphocytes are not produced enough by the bone marrow;
• AIDS virus;
• oncological diseases;
• taking glucocorticosteroid drugs;
• hyperactivity of the adrenal cortex;
• multiple sclerosis;
• myasthenia gravis;
• Guillain-Barre syndrome.

All parents worry about the health of their children, and therefore at the first sign of influenza or ARVI, they rush to the clinic, where the pediatrician prescribes a blood test for the baby. This is where the first questions arise regarding the interpretation of the analyses. For example, caring fathers and mothers are very concerned about what an increase in lymphocytes in a child’s blood indicates, how dangerous it is, and what actions need to be taken to normalize this indicator? We will try to answer all your questions in this article.

Meet the lymphocytes

Our blood contains cells that are important for the functioning of the body called lymphocytes. They are a type of leukocytes (white blood cells), and are responsible for the state of immunity, which means they are designed to fight any infectious agents that enter the body. Naturally, when bacteria and viruses enter, the body reacts sharp increase the production of “protective” cells, which, in fact, is what a blood test shows. In this regard, a high level of lymphocytes in the blood indicates that an infection has settled in the baby’s body.

However, lymphocytes do more than simply signal the presence of infection. They monitor pathogenic agents (viral, bacterial or even cancer) that appear in the body, produce antibodies to destroy them, and even manage the process of removing pathogenic microflora from the body. In addition, lymphocytes produce immunoglobulins - protein compounds, from which immunity to various diseases is subsequently formed.

What determines the increase in lymphocytes

Increasing the level of “immune” cells does not at all mean that the more white blood cells in the body, the better for health. Rather, it speaks about the level infectious infection(the stronger the inflammatory process, the higher the level of lymphocytes in the blood). Moreover, even when the disease is defeated, the number of lymphocytes in the blood will remain elevated throughout the entire recovery period. In this case, there is no need to be afraid of an overestimated indicator, since it means that immunity to infectious agents is being formed in the body.

In medicine, an increase in the level of the cells in question in the blood is called lymphocytosis. Moreover, depending on the cause that provoked this condition, lymphocytosis is divided into absolute and relative. Absolute is characterized by the number of cells in question per 1 liter of blood. This indicator is exceeded less often, and therefore it is not given as much attention as relative lymphocytosis. With it, the total number of protective cells remains normal, however, due to changes in the number of other white blood cells, the total percentage of lymphocytes increases (there are fewer other cells, and more lymphocytes, as a percentage). Let's give a few examples.

An increase in the level of the cells in question often occurs against the background of a decrease in the number of neutrophils (the largest group of cells belonging to leukocytes). This can happen as a result of infection in the body or due to taking certain medications.

If, according to the test results, lymphocytes are decreased, but segmented (mature) neutrophils are increased, it means that the disease has already receded and time is required for the child’s body to fully recover. As soon as this happens, the tests will immediately return to normal.

When a child has elevated lymphocytes, there is high ESR, and besides, the temperature does not go down, there is every reason to believe that he was struck by an acute viral infection. In this case, the doctor prescribes little patient taking medications containing interferon.

In the case of elevated levels of lymphocytes and monocytes (another representatives of white blood cells responsible for removing dead microbes from the body), the child is diagnosed with chronic viral infection.

Note that if the baby has recently suffered a viral infection, the level of lymphocytes in his body may remain quite high for some time. If except this indicator There are no health complaints, you don’t have to worry about the baby’s condition. After approximately 2-3 weeks, the level of these blood components returns to normal. True in some cases increased level lymphocytes can persist for 1-2 months. In this case, a month later the young patient will have to take a repeat blood test.

Norm of lymphocytes

It should be said that many parents one-year-old babies they get scared when they see in a blood test an increased level of the cells in question, seriously exceeding the norm. Let’s say right away that there is no mistake here, just as there is no pathology, because a high level of lymphocytes in children in the first years of life is considered the norm. Just them the immune system She is still immature, but with age she will definitely return to normal.

At birth, the level of lymphocytes is 25% of all white blood cells.

• By 1 year of life, the limit of the relative norm of lymphocytes increases to 45–65%.
• During the period of 1–2 years this norm decreases slightly and varies between 37–60%.
• From 2 to 4 years the norm should be in the range of 33–50%.
• Over the period of 5–10 years, their level in the blood practically does not change and is equal to 30–50%.
• From 10 to 16 years of age, this norm is as close as possible to the indicators of adults and amounts to 30–45%.

Thus, we can talk about the development of lymphocytosis in a child only if tests show an excess of generally accepted age norms:

• 65% in 1 year;
• 55% at 5 years;
• 45% at 10 years.

Causes of lymphocytosis

So, we found out that lymphocytosis can be natural physiological process in children in infancy and indicates the strengthening of the baby’s immunity. However, if the level of these white blood cells in a newborn exceeds all acceptable limits or lymphocytosis is detected in an older child, it is necessary to understand the causes of this phenomenon.

In medicine, lymphocytosis is usually divided into two types:

• malignant (if the increase in lymphocytes is caused by the appearance of cancer cells);
• reactive (develops when the body is damaged by viruses, bacteria and protozoan microorganisms).

The malignant type of lymphocytosis is quite rare, but it can appear even in infants (this can never be ruled out). As a rule, on malignant disease will indicate associated symptoms, such as pallor, weakness, anemia and frequent nosebleeds, fever and enlarged lymph nodes, joint pain, frequent infections and the presence of lymphoblasts in the blood. A number of studies that the doctor will prescribe will help confirm or refute the suspicion of cancer.

From oncological diseases blood children most often face acute lymphoblastic leukemia(ALL), and adults – with chronic lymphocytic leukemia(HLL). It is gratifying that if detected in a timely manner, these are fatal. dangerous diseases are treatable, which means that therapy started on time leaves such patients with good chances for future life.

Much more often, children experience an increase in lymphocytes, which indicate that an infection is developing in the child’s body. Typically this is:

Especially often the level of “immune” cells in children increases in the case of infectious mononucleosis, however, other reasons cannot be excluded.

At the same time, there are non-infectious causes high level studied blood cells. These include:

• autoimmune diseases (Crohn's disease, rheumatism and others);
• endocrine disorders, as well as hormonal changes in the body (diffuse toxic goiter);
• poisoning with chemicals and harmful metals (lead, arsenic, etc.);
• treatment with certain medications (antibacterial, hormonal, analgesics, valproic acid, levomycetin);
• splenectomy;
• vaccination;
• avitaminosis;
• injuries;
• stress.

In some cases, a slight increase in this indicator in children may be observed against the background physical activity(which often happens with children involved in sports sections).

Lymphocytes are white blood cells responsible for the body's immune defense. They belong to the leukocytes, along with eosinophils, neutrophils, etc. The structure of a lymphocyte involves a large nucleus and a small layer of plasma, without the presence of granules, which is why they are called agranulocytes. Deviation from the norm of lymphocytes in the blood in children may indicate various kinds diseases, so it is important for parents to be able to analyze the results not only with the help of a doctor, but also on their own.

The norm of lymphocytes in the blood of a child

If in adults the level of lymphocytes, accepted as the norm, remains unchanged throughout life, then the norm of lymphocytes in children varies up to 16 years.

There are absolute and relative indicators, the first measures the number of blood cells in the blood volume, the second - the proportion of lymphocytes from the total number of leukocytes (all white protective cells).

The norm of lymphocytes in children under one year of age is 45-70% (relative), 2-11*10 9 /l (absolute).

The norm of lymphocytes in children 1 - 2 years old is slightly less: 37-60%, 3-9.4 * 10 9 / l.

From 2 to 4 years, the relative indicator should fall within the range from 33 to 50%, and the absolute indicator from 2 * 10 9 / l to 8 * 10 9 / l.

4-10 years: 30-50%, 1.5-6.9*10 9 /l.

11-16 years: 30-45%, 1.2-5.2*10 9 /l.

The norm of lymphocytes in children under one year old can be considered in more detail, because immediately after birth, the baby’s body gradually adapts to the surrounding conditions:

Newborns: 15-35%

Up to a week: 21-55%

1 week – year: 45-70%

When a child is born, the level of neutrophils in the blood is especially high, but after 5 days the level of lymphocytes reaches about 40%. This condition persists for up to 4 years, after which a physiological “crossover” occurs, and the number of neutrophils and leukocytes becomes approximately equal. Later, there are more neutrophils.

Age must be taken into account when making a diagnosis; for example, lymphocytes of 60 in a child can be both normal and a sign of lymphocytosis.

Types of lymphocytes

Lymphocytes, like most of the body's protective cells, are formed in bone marrow, circulate through the bloodstream for several hours and then move to various tissues. Depending on their functions and further location, lymphocytes are classified into several types:

1. B lymphocytes

Localized in lymph nodes and make up approximately 15% of total number. B-lymphocytes, encountering a pathogenic cell on their way, record information about it and adapt to destroy similar cells. It is thanks to them that the results of vaccinations and emerging immunity to successfully cured diseases are possible.

1. T lymphocytes

The prefix “T” characterizes the location of these lymphocytes - the thymus. About 80% of all lymphocytes are concentrated here. In turn, T-cells are divided into T-killers (from English to kill), T-helpers (from English to help), T-suppressors (from English to suppress).
T-killers do all the “dirty” work, directly destroying dangerous agents.
T helper cells contribute normal operation T-killer cells, releasing certain substances.
T-suppressors regulate and partially suppress the defense response to prevent mass destruction healthy cells.

1. NK lymphocytes

From English NK – natural killers (natural killers or rather “natural killers”), their task is to destroy their own, infected and cancer cells. Their share is 5-10% of the total.

High lymphocytes in the blood of a child

A condition in which the level of lymphocytes goes off scale is called lymphocytosis. The reasons that can cause are divided into two groups.

1. Jet

Reactive causes of lymphocytosis in children are especially common, because they include diseases that are enough to be suffered once in a lifetime: measles, chicken pox, rubella, mononucleosis, etc.

In addition, an increase in lymphocytes in a child’s blood may indicate:

• ARVI;
• Tuberculosis;
• Syphilis;
• Acute leukemia;
• Reaction to some medications;
• Bronchial asthma;
• Hepatitis;
• Endocrine diseases(myxedema, Addison's disease, etc.);
• And etc.

Lymphocytosis in children does not always indicate a disease; the level of lymphocytes may increase after a successful fight against the virus, that is, lymphocytosis in this case indicates recovery.

1. Oncological

The second group of reasons that lymphocytes in the blood of a child or adult are enlarged is associated with the formation malignant tumors.

Lymphocytes are the only blood cells capable of destroying own cells that have been infected or mutated. They are the ones responsible for fighting malignant tumors.

Lymphocytosis in a child is most often provoked by the body’s reaction to a virus, infection or bacteria, that is, the first group of factors. However, even experienced doctor, based only on the results of a blood test, is unlikely to reliably refute cancer.

Low lymphocytes in the child's blood

A condition in which there are fewer lymphocytes in the blood than there should be – lymphopenia.

Relative lymphopenia is associated with an increased content of neutrophils in the blood. This occurs in various purulent and infectious diseases.

Absolute lymphopenia is caused by inhibition of lymphocyte production; one of the reasons that provokes it may be HIV.

Diseases in which the level of lymphocytes in the blood decreases:

• Tuberculosis;
• Pneumonia;
• Autoimmune diseases(lupus erythematosus);
• Aplastic anemia;
• Terminal stage oncological diseases;
• Some medical procedures(radiotherapy and chemotherapy, glucocorticoids).

Change in lymphocytes

In laboratory conditions, not only the number of lymphocytes is analyzed, but also some of their other parameters.

For example, what is “plasmatization of the cytoplasm of lymphocytes” in a child? This comment from the laboratory technician indicates that the structure of the lymphocytes has changed. This may occur due to the child’s recovery from infectious diseases, due to the presence of oncology or mononucleosis. If other tests are normal, most likely plasmatization has persisted as a consequence past illness. Donate blood for analysis after a month, this indicator should normalize.

Atypical lymphocytes in a child are cells that have larger size, incorrect oval shape and a smaller nucleus than normal cells.

Changes in appearance lymphocytes does not affect their functions. At the time of illness, the production of lymphocytes in the bone marrow occurs at a faster rate, as a result of which the cells do not have time to mature properly, which is reflected in the distorted appearance.

Atypical lymphocytes appear in the blood under the same conditions as lymphocytosis; when paired with wide-plasma lymphocytes in a child, they probably indicate mononucleosis.

It is advisable for parents to have basic knowledge about the norm of lymphocytes in the blood and other cells in children, because the pediatrician may not pay attention to some details of the tests, much less explain all the details to you.

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