Brief 1.definition bleeding of skin, mucous and organs 2. cause: (1)production :I drug, tumor, infection, adiation (2)destruction :t ITP, DIC, TTP (3)abnormal distribution: splenomegaly 3.classification primary secondaryBrief 1.definition：bleeding of skin、mucous and organs 2.cause： （1）production ：drug, tumor, infection, radiation （2）destruction ：ITP,DIC,TTP （3）abnormal distribution：splenomegaly 3.classification：primary ,secondary