Platelets are a type of tangible component of blood, which are slightly concave on both sides, oval or disc-shaped, and mainly serve to stop bleeding. When a blood vessel is broken due to injury or other reasons, a large number of platelets will immediately gather at the broken area and form a clot to block the blood vessel; in addition, platelets also release substances that cause blood vessels to contract and blood to clot, preventing blood from flowing out of the broken area. To use an analogy, platelets are like sandbags that we use to block the flood when the dam breaks, and they carry the burden of rescue and assault. The human blood “platelets”, a normal person per cubic millimeter of blood contains about 100 – 300,000 platelets, its life expectancy is an average of 8 – 12 days, due to a variety of A platelet count result below the lower limit of the reference value is thrombocytopenia. Depending on the degree of thrombocytopenia, different clinical manifestations may occur: in mild cases, there may be bleeding spots and bruises on the skin, blood oozing from the gums and epistaxis, while in severe cases, there may be bleeding from organs: such as vomiting blood, black stools, hematuria and brain hemorrhage. There are many factors that can cause thrombocytopenia, and the main factors are as follows: 1. Decreased platelet production (1) hereditary: In a few cases, there is a correlation between thrombocytopenia and heredity, and common hereditary disorders of thrombocytopenia include congenital simple anaplastic thrombocytopenic purpura and thrombocytopenia caused by Fanconi anemia. (2) Acquired: Platelets are produced by megakaryocytes in the bone marrow, and any factor that can affect the production of megakaryocytes in the bone marrow can cause a decrease in platelet production. For example, aplastic anemia caused by abnormal bone marrow hematopoietic stem cells; thrombocytopenia caused by the lack of vitamin B12, folic acid deficiency and other hematopoietic raw materials; various malignant tumors on the bone marrow (malignant tumor bone marrow metastasis, leukemia, myelodysplastic syndrome, myelofibrosis), as well as bacterial and viral infections, ionizing radiation, chemotherapeutic drugs and other factors can cause damage to hematopoietic stem cells, resulting in Thrombocytopenia. (1) Increased platelet destruction caused by immune factors The production and metabolism of platelets in the body is relatively balanced, but in some disease conditions, the patient’s body produces antibodies against their own platelets, these antibodies and platelets combined, so that the sensitized platelets in the monocyte macrophage system is phagocytosed and destroyed, resulting in thrombocytopenia. The common ones are immune thrombocytopenic purpura, HIV infection, systemic lupus erythematosus, rheumatoid arthritis, hyperthyroidism, chronic hepatitis, and drug-induced thrombocytopenia (such as heparin, quinine, quinidine, antipyretics, penicillin, cephalosporin antibiotics, rifampin, furosemide, carbamazepine, sodium valproate, sulfonylurea hypoglycemic agents and phenytoin sodium, etc.). (2) Increased platelet destruction caused by non-immune factors Commonly include diffuse intravascular coagulation, thrombotic thrombocytopenic purpura, infection, etc. (3) Abnormal platelet distribution When splenomegaly and hypersplenism are caused by various reasons such as liver cirrhosis and myelofibrosis, a large number of platelets are stored in the spleen, which can also cause peripheral thrombocytopenia. 4. Other causes such as bleeding, hemodialysis and other causes of platelet loss can also lead to thrombocytopenia. In short, there are many possible causes of thrombocytopenia, the first thing you should do is to find a specialist to identify the cause and take reasonable treatment according to different situations. When platelets are very low, you should also pay attention to: avoid strenuous activities, bed rest when extremely low; keep emotional stability is very important; avoid trauma; anti-platelet drugs being applied to treat other diseases such as aspirin, bimatoprost, clopidogrel or blood-stasis activating drugs should be discontinued; avoid spicy and strong food to avoid aggravating the condition.