The causes of thrombocytopenia, mainly include: 1, insufficient platelet production, such as aplastic anemia, acute leukemia and infection, or due to toxic substances, drugs, such as benzene, xylene, cyclophosphamide and other harmful substances acting in the bone marrow, the proliferation or growth and maturation of polymeric cells in the bone marrow is impaired, it causes insufficient platelet production and a decrease in the number of platelets; 2, excessive destruction of platelets, seen in Some drugs, such as sulfonamide, chloramphenicol, aminopyrine and other common drug action or infection, through the immune mechanism of the body to produce anti-platelet antibodies, resulting in excessive destruction of the body’s platelets and a decrease in the number of platelets. It can also be seen in primary immune thrombocytopenia (ITP), diffuse intravascular coagulation (DIC), thrombotic thrombocytopenia (TTP), and heparin-induced thrombocytopenia, systemic lupus erythematosus, and HIV-associated thrombocytopenia; 3. Abnormal platelet distribution, mainly most commonly when hypersplenism is caused by various reasons, or when splenomegaly is present. Excessive platelet retention in the spleen can significantly reduce the number of platelets in the blood.