Thrombocytopenia (synonym trombopenia) is a decrease in the number of platelets in the blood. Distinguish between physiological and pathological thrombocytopenia. Physiological thrombocytopenia, occurring during sleep, after a meal, menstrual period, usually does not reach high levels. Pathological thrombocytopenia may depend on reduced education, heightened destruction or increased consumption of platelets. Low education platelets observed in the contraction zone blood on the soil osteosclerosis, growth of abnormal tissue (for example, with leukaemia, bone marrow fibrosis after exposure to ionizing radiation, toxic lesion of the bone marrow (uremia, benzene poisoning). The increased destruction of platelets is celebrated on the soil of allergies to medicines. In this case, develop autoimmune processes by which the body produces protivomaljarijnye antibodies. The increased destruction of platelets may be due to increased activity of the spleen; its removal results in a mild thrombocytopenia. High consumption of platelets observed in the extensive formation of blood clots. The consequence of thrombocytopenia is the tendency to bleeding. The most striking manifestation of thrombocytopenia is thrombocytopenic purpura (see).