Thrombocyte parameters of blood - Causes, symptoms and treatment. MF.

Platelets( blood plates, platelets) are blood elements that participate in hemostasis.

Platelets are small, denuclearized cells, oval or round;their diameter is 2-4 microns. Thrombocyte precursors are megakaryocytes. In blood vessels, platelets can be located at the walls and in the bloodstream. In a calm state( in the bloodstream), the platelets have a disk-like shape. When cells are activated, platelets acquire sphericity and form special outgrowths( pseudopodia).With the help of such outgrowths, the blood plates can stick together or adhere to the damaged vascular wall. Platelets have the following abilities: to aggregation, adhesion, degranulation, retraction of the clot. On their surface, they can transfer coagulation factors( fibrinogen), anticoagulants, biologically active substances( serotonin), and circulating immune complexes. Adhesion and aggregation of platelets allow to provide hemostasis in small vessels: they accumulate in the area of ​​damage, adhere to the damaged wall. Stimulators of platelet aggregation are thrombin, adrenaline, serotonin, collagen. Thrombin causes aggregation of the blood platelets and the formation of pseudopodia. Platelet granules contain clotting factors, peroxidase enzyme, serotonin, calcium ions Ca2 +, ADP( adenosine diphosphate), von Willebrand factor, platelet fibrinogen, platelet growth factor. Retraction of the blood clot is a property of platelets to tightening the thrombus and squeezing the serum. In this case, platelets adhere to the fibers of fibrin and release thrombostenin, which precipitates on the filaments of fibrin, as a result of which the latter are condensed and twisted forming a primary thrombus. The number of platelets varies depending on the time of day, and also throughout the year. Physiological decline in platelet levels is noted during menstruation and during pregnancy, and a rise after physical exertion.

Units of measurement: kcal / μL( x 10 3 cells / μl).
Alternative units of measurement: x 109 cells / liter.
Conversion factors: x 109 cells / L = x 10 3 cells / μL = Thousand / μL.
Reference values: 150 - 400 thousand / μL.

Increased level( thrombocytosis):

functional( reactive) thrombocytosis - temporary, caused by activation of hematopoiesis:

1. splenectomy;
2. inflammatory processes( systemic inflammatory diseases, osteomyelitis, tuberculosis);
3. anemia of different genesis( after hemorrhage, iron deficiency, hemolytic);
4. condition after surgery;
5. oncological diseases( cancer, lymphoma);
6. physical overvoltage;
7. acute hemorrhage or hemolysis;

tumor thrombocytosis:

1. myeloproliferative disorders( myeloid leukemia);
2. idiopathic hemorrhagic thrombocythemia;
3. Erythremia.

Lowering of the level( thrombocytopenia):

congenital thrombocytopenia:

1. Wiskott-Aldrich syndrome;
2. Chediak-Higashi syndrome;
3. Fanconi syndrome;
4. anomaly of Mei - Hegglina;
5. Bernard-Soulier syndrome( giant platelets).

acquired thrombocytopenia:

1. idiopathic autoimmune thrombocytopenic purpura;
2. drug thrombocytopenia;
3. systemic lupus erythematosus;
4. thrombocytopenia associated with infection( viral and bacterial infections, rickettsiosis, malaria, toxoplasmosis);
5. splenomegaly;
6. aplastic anemia and myelothesis( replacement of bone marrow with tumor cells or fibrous tissue);
7. metastasis of tumors in the bone marrow;
8. megaloblastic anemia;
9. paroxysmal nocturnal hemoglobinuria;
10. Evans syndrome( autoimmune hemolytic anemia and thrombocytopenia);
11. DIC-syndrome( disseminated intravascular coagulation);
12. massive blood transfusion, extracorporeal circulation;
13. during neonatal period( prematurity, hemolytic disease of newborns, neonatal autoimmune thrombocytopenic purpura);
14. congestive heart failure;
15. Fisher-Evans syndrome;
16. thrombosis of renal veins.