Thrombocytes: normal in children. Platelet blood analysis: interpretation and interpretation of results

Blood cells are quite diverse. Each of them performs its specific role, aimed at maintaining and maintaining the body's functions. Thrombocytes are responsible for protecting the body from blood loss.

It is especially important to determine the number of these cells in children, because they are more prone to injury, and blood loss with them can affect the body much more than an adult. So what is a platelet, and what is the norm of platelets in children?

What are these cells?

Platelets refer to cells that ensure the integrity of the walls of blood vessels. They are formed from a megakaryocyte - a giant cell devoid of a nucleus. The formation of blood platelets (the second name of platelets) occurs by detaching them from a giant cell.

In the vessels circulates about 70 percent of all the cells formed, and 30 percent remains in the spleen. There is also the destruction of these cells.

Platelets do not have nuclei, and due to this they are not capable of reproduction.

Their cytoplasm contains a number of enzymes, as well as substances that contribute to the formation of thrombi, due to which these cells and perform their functions.

Platelets live shortly - from 7 to 10 days, after which unused cells are destroyed by macrophages.

The norm of platelets in children is always somewhat greater than in adults. This is due to the active metabolism of the child's body. What are the normal values of the number of these cells?

Normal performance

How many of the detectable blood cells should be platelets? Norms in children usually lie within the following limits:

• In newborns, the number of blood platelets usually ranges from 100 to 420 * 10⁹ cells per liter of blood.
• At the age of up to one year, the minimum number of platelets increases slightly - up to 150. The maximum, on the contrary, decreases to 350.
• After a year, the child's platelet index is the same as in an adult - 180-320 * 10⁹ per liter of blood.
• At the age of five, a certain phenomenon is sometimes observed: platelets vary (the norm in children of 5 years does not differ from adult indices, however, the cells become more active, which causes the development of thrombopathies). This phenomenon is explained by the second pediatric crosshair. Due to the dominance of neutrophils, inflammation processes with a false activation of platelets can be triggered.

It should be remembered that with a hardware blood test and with manual calculation, the norm of platelets in the blood of a child may vary slightly. Therefore, with automatic counting, the maximum normal values of plates up to 500 in newborns and up to 400 in a one-year-old child are permissible.

Preference should still be given to manual calculation: less chance to make a mistake and more - to put the right diagnosis.

How are they formed?

The formation of blood platelets occurs in the bone marrow. The progenitor of these cells is a megakaryocyte - a giant cell. It is located between endothelial cells and fibroblasts. Due to the action of these cells, the particles of the megakaryocyte are separated from the outside (the cytoplasm passes between the surrounding cells and thus is unscrewed).

Entering the bloodstream, thrombocytes circulate through it until they reach the damaged portion of the vessel (it is important that the endothelium is damaged). After settling there, the blood plates start some humoral processes, as a result of which a fibrous skeleton is formed on the lesion site, on which new platelets settle. Thus, a white and then a red blood clot forms first.

The process of the formation of cells in the bone marrow occurs daily, which allows to maintain their normal number. Any damage to the bone marrow helps reduce or increase the number of plates.

Changes in the number of cells

As you know, all indicators of the internal environment of the human body change under the influence of various reasons. An increase in platelet count is called thrombocytosis. It can be subdivided into primary and secondary. Primary thrombocytosis develops as a result of direct damage to the bone marrow. The secondary depends on the concomitant diseases.

Decreased platelet count is called leukopenia. As well as thrombocytosis, it is divided into primary and secondary.

It is necessary to understand how the platelets in children vary. The norm (the table includes normal indicators and deviations according to age) can be changed in any of the parties and sometimes it is wrong to be assessed. That is why it is extremely important to know the possible deviations from the norm in children for the correct diagnosis. The table is as follows.

So why are the levels of these cells changing? It is necessary to understand this problem in more detail.

The causes of increased platelet count

Why can platelets grow? The norm in children may vary due to the following reasons:

• Myeloproliferative diseases (usually tumor lesions of the bone marrow with increasing its functional activity). An increase in the number of platelets occurs most often with a parallel increase in other cells.
• Inflammatory diseases, usually of a chronic nature, are rheumatoid joint damage (juvenile arthritis), tuberculosis.
• Bleeding. There is a functional hyperproduction of platelets to stop blood loss.
• Use of glucocorticosteroids. These hormones with prolonged use (for example, with severe bronchial asthma) contribute to the fact that almost all natural processes are violated, therefore thrombocytosis can take place.

Platelets above normal in the child can be observed and as a result of diseases of the blood system (for example, with erythremia).

Decreased blood plate count

As it was said, the level of coagulating cells may decrease. Why is this happening?

Platelets below the norm in a child are most often observed with blood diseases - aplastic anemia and leukemia. The number of cells of the immune system also decreases.

Hereditary diseases. These include Wiskott-Aldrich Syndrome, Fanconi, histiocytosis. It is these diseases that lead to the fact that children have reduced platelets. Norm in children is almost never observed, the level of plates is always reduced.

Menses. They are the cause of thrombopenia in girls who have recently had menarche. Prior to the normalization of the cycle, a significant decrease in the level of cells can be observed.

Heavy metal poisoning. The most common is lead poisoning (for example, a case where the child had this poisoning as a result of evaporation of vapors from new wallpaper is known).

Features in children

Platelet counts normally normalize to one year, but during the neonatal period, the child 's blood system undergoes some changes.

When the platelets are determined, the norm in children up to a year may vary somewhat. For example, during the first five hours of life, the baby has about 215 million platelets in his blood. During the first five days this amount decreases, and by the end of the 5th day their number has stopped at 175 million. On the 5th day there are significant changes in blood - the level of not only platelets, but also leukocytes (the so-called "pediatric scissors" - the cross between lymphocytes and neutrophils) changes. Approximately from the tenth day, the platelet count is stabilized - at least 100 million cells (100-420 * 10⁹).

As they grow older, their number increases slightly and about a year becomes equal to 180-320 * 10.

How to determine platelets?

A blood test is used to determine the number of blood plates. You can conduct it in any clinic or laboratory, equipped with the necessary equipment.

During the analysis, you must take into account the age of the child. It should be remembered that if the platelets are determined, the norm in children under one year, namely, its lower limit, is rather low. To panic it is necessary only if the bottom indicator is less than 100.

Indications for the definition of cells are prolonged bleeding or, conversely, excessively rapid formation of thrombi.

As it was said above, if the platelets are determined, the norm in children may fluctuate slightly depending on the method of counting. If automated counting is used, the upper limit of the rate is slightly higher than for manual counting. This is due to the fact that the device perceives even small clots of blood as several blood clots, and a person counts as one cage.

In addition to determining the number of cells, their functional activity can be assessed. To do this, another study is assigned - a coagulogram. It can detect abnormalities in the work of plates, even if the norm of platelets in the blood of the child has been determined.

How dangerous is the change in normal indicators?

What is the level of thrombus-forming elements of the blood? Their definition is important in the following cases:

• A low level of cells promotes an increased risk of bleeding. When an injury is received, the likelihood of large blood loss increases significantly (and for a child the loss of even a small amount of blood can become fatal). Usually precursors of reducing the level of cells are bruises on the skin even after easy contact with it. When they appear, you should definitely take an analysis for platelets.
• An increase in the level of cells threatens with increased thrombus formation, which can adversely affect the blood circulation as a whole (the probability of thrombosis and subsequent stroke, heart attack or necrosis increases).

That is why it is extremely important to determine these blood elements.