thrombocytopenic purpura thrombocytopenic purpura thrombocytopenic purpura are purpura associated with a reduction in circulating blood platelets which can result from a variety of causes, such as kaposi sarcoma. thrombocytopenic purpurapurpuraspecialtyimmunology, hematology types by tradition, the term idiopathic thrombocytopenic purpura is used when the cause is idiopathic. however, most cases are now considered to be immune-mediated. another form is thrombotic thrombocytopenic purpura. diagnosis diagnosis is done by the help of symptoms and only blood count abnormality is thrombocytopenia. treatment