Blood cells are quite diverse.Each of them performs its specific role, aimed at preserving and maintaining the body's functions. Thrombocytes are responsible for protecting the body from blood loss.
It is especially important to determine the amount of datacells in children, because they are more prone to injury, and blood loss in them can affect the body is much stronger than in 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 providethe integrity of the walls of the 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 certain amount of enzymes, as well as substances that contribute to the formation of blood clots, due to which these cells and carry out their functions.
Platelets do not live long - from 7 to 10 days, after which unused cells are destroyed by macrophages.
The rate of platelets in children is always slightly higher 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
What number among the blood cells to be determined should be platelets? The norm in children usually lies within the following limits:
- In newborns, the number of platelets is usually from 100 to 420 * 10⁹ cells per liter of blood.
- At the age of one year, the minimum number of platelets slightly increases - up to 150. The maximum, on the contrary, decreases to 350.
- After a year, the child's platelet index is the same as that of an adult - 180-320 * 10⁹ per liter of blood.
- At the age of five is sometimes observeda certain phenomenon - platelets change (the norm in children 5 years old does not differ from adult indicators, but the cells become more active, which is why the development of thrombopathies is observed). This phenomenon is explained by the second pediatric crossing. Due to the dominance of neutrophils, inflammation processes with false platelet activation can be triggered.
It should be remembered that with hardware researchblood and the manual calculation of the rate of platelets in the blood of a child may vary somewhat. 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: there is less likelihood to make a mistake and more - to make a correct diagnosis.
How are they formed?
The formation of blood platelets occurs inbone marrow. The ancestor of these cells, the megakaryocyte, is a giant cell. It is located between the endothelial cells and fibroblasts. Due to the impact of these cells from the outside, the particles of the megakaryocyte are separated (its cytoplasm passes between the surrounding cells and is thus detached).
When leaving the bloodstream, platelets circulate throughhim until they fall on the damaged area of the vessel (it is important that there is damage to the endothelium). When they settle there, the blood plates trigger some humoral processes, as a result of which a fibrous skeleton is formed at the site of the lesion, on which new platelets settle. Thus a white thrombus forms first, then a red thrombus.
The process of cell formation in the bone marrowoccurs daily, which allows you to maintain their normal amount. Any damage to the bone marrow helps to reduce or increase the number of plates.
Cell number changes
As is known, all indicators of the internal environmentthe human body changes under the influence of certain reasons. An increase in platelet count is called thrombocytosis. It can be divided into primary and secondary. Primary thrombocytosis develops as a result of direct damage to the bone marrow. Secondary depends on concomitant diseases.
Platelet count is called leukopenia. As well as thrombocytosis, it is divided into primary and secondary.
It should be figured out how to varyplatelets in children. The norm (the table includes normal indicators and deviations according to age) can change in any of the parties and sometimes be regarded incorrectly. 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.
| Index | Thrombocytopenia | Norm | Thrombocytosis |
| first 5 days of life | <420 * 10⁹ | 215-420 * 10⁹ | > 420 * 10⁹ |
| 10-14 days | <175 * 10⁹ | 175-420 * 10⁹ | > 420 * 10⁹ |
| 1 year | <150 * 10⁹ | 150-350 * 10⁹ | > 350 * 10⁹ |
So why change the levels of these cells? It is necessary to understand this problem in more detail.
Causes of Platelet Rises
Why can platelets increase? The norm in children may vary due to the following reasons:
- Миелопролиферативные заболевания (обычно tumor lesions of the bone marrow with an increase in 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 - rheumatoid joint damage (juvenile arthritis), tuberculosis.
- Bleeding There is a functional hyperproduction of platelets to stop blood loss.
- Использование глюкокортикостероидов.These hormones with prolonged use (for example, in severe bronchial asthma) contribute to the fact that almost all natural processes are disrupted, so thrombocytosis may occur.
Platelets above the norm in a child can also be observed as a result of diseases of the blood system (for example, with erythremia).
Reducing the number of platelets
As mentioned above, the level of coagulation cells may decrease. Why is this happening?
Platelets below normal are most often seen in children with blood disorders - aplastic anemia and leukemia. The number of cells in the immune system is also decreasing.
Hereditary diseases.These include Wiscott-Aldrich syndrome, Fanconi, histiocytosis. These diseases lead to the fact that children have reduced platelets. The rate in children is almost never observed, the level of the plates is always reduced.
Menses. They are the cause of thrombopenia in girls who have recently had menarche. Before the cycle is normalized, a significant decrease in cell level can be observed.
Heavy metal poisoning. Lead poisoning is most common (for example, there is a case when a child has had this poisoning as a result of the evaporation of vapor from new wallpaper).
Features in children
Platelet counts usually normalize to one year, but during the neonatal period, the baby’s blood system undergoes some changes.
When platelets are determined, the rate in children is up toyears may vary somewhat. For example, during the first five hours of life, about 215 million platelets are observed in a baby’s blood. During the first five days, this number decreases, and by the end of 5 days their number stops at 175 million. It is on the 5th day that significant changes occur in the blood - the level of not only platelets, but also of leukocytes changes (the so-called “pediatric scissors” - the crossing of lymphocytes and neutrophils). Approximately from the tenth day the platelet count stabilizes - at least 100 million cells (100-420 * 10⁹).
As they grow older, their number slightly increases and becomes equal to 180-320 * 10⁹ for about a year.
How to determine platelets?
A blood test is used to determine the number of platelets. You can hold it in any clinic or laboratory equipped with the necessary equipment.
When analyzing it is imperativetake into account the age of the child. It should be remembered that if platelets are determined, the rate in children under one year old, namely its lower limit, is rather low. It is worth panicing only if the lower indicator is less than 100.
The indications for the determination of cells are prolonged bleeding or, conversely, an excessively rapid thrombus formation.
As stated above, if determinedplatelets, the rate in children may vary slightly depending on the method of counting. If automated counting is used, the upper limit of the rate is slightly higher than with manual counting. This is due to the fact that the device perceives even small blood clots as several blood clots, and the person when counting - as one cell.
Помимо определения количества клеток, можно evaluate their functional activity. To do this, another study is assigned - coagulogram. It can reveal violations in the work of the plates, even if the rate of platelets in the child’s blood has been determined.
What is dangerous about changing normal values?
What is the level of thrombogen-forming blood elements for? Their definition is important in the following cases:
- Low cell levels increase riskbleeding. In the event of injury, the likelihood of large blood loss increases significantly (and for a child even the loss of a small amount of blood can be fatal). Usually the harbingers of lowering the level of cells are bruises on the skin, even after light contact with it. When they appear, be sure to pass an analysis of platelets.
- An increase in the level of cells threatens to increasethrombus formation, which may adversely affect the blood circulation in general (increases the likelihood of thrombosis and subsequent stroke, heart attack or necrosis).
That is why it is extremely important to determine these blood elements.
