Thrombocytopenia in severe infections is actually a complication of severe infections for the following reasons: 1, there is a bone marrow suppression in the complications of severe infections, which is the most common cause of thrombocytopenia; 2, bacteria and metabolites can activate the body’s complement to destroy platelets through the immune pathway; 3, bacterial endotoxin damage to the vascular endothelium, there is direct damage to platelets, so that platelet destruction 4, bacterial endotoxin and hematopoietic negative regulatory factors on the inhibition of bone marrow megakaryocytes, resulting in reduced platelet production; 5, some patients also have anti-platelet antibodies in the body, resulting in increased platelet destruction; 6, due to severe infection leading to disseminated intravascular coagulation, can also lead to increased platelet destruction; 7, currently can not find the cause of the so-called hemophagocytic syndrome, once in severe infection Once the hemophagocytic syndrome occurs, the patient is often difficult to treat, and the cure rate is only about 10%-20%, with a very high mortality rate; 8, in the process of treatment, such as patients with severe infections need to do hemodialysis, do blood purification, also due to blood purification, the destruction of platelets, is also a cause of platelet reduction.