2. Is diagnosed as immune thrombocytopenia according to the criteria of ICD-10, i.e., platelet < 100×109/L for at least two hematology tests with normal blood cell morphology; skin petechia, ecchymosis and (or) the clinical manifestations of mucosa and visceral hemorrhage; no splenomegaly; exclusion of other secondary thrombocytopenia, such as aplastic leukemia, aplastic anemia characterized by thrombocytopenia as the first hematologic abnormality, hereditary thrombocytopenia, thrombocytopenia secondary to other autoimmune diseases, infections or drugs etc...