Then, the secondary causes (usually 5-10% of suspected ITP cases) should be excluded. Secondary causes could be leukemia , medications (e.g. quinine , heparin ), lupus erythematosus , cirrhosis , HIV]], [[hepatitis C, congenital causes, antiphospholipid syndrome , von Willebrand factor deficiency and others. In approximately 1% of cases autoimmune hemolytic anemia