General Considerations 1.definition: thrombocyte unrelated to a drug, an infection, or autoimmune disease is generally classified as ITP 2 character: shortened span of platelet increased megakaryocyte in bone marrow 3 classification: acute, chronicGeneral Considerations 1.definition：thrombocyte unrelated to a drug, an infection, or autoimmune disease is generally classified as ITP 2.character： shortened span of platelet increased megakaryocyte in bone marrow 3.classification：acute, chronic