immune thrombocytopenia

A condition in which platelets (blood cells that cause blood clots to form) are destroyed by the immune system. The low platelet count causes easy bruising and bleeding, which may be seen as purple areas in the skin, mucous membranes, and outer linings of organs. Also called idiopathic thrombocytopenic purpura, immune thrombocytopenic purpura, and ITP.