Thrombotic Microangiopathies: Role of ADAMTS-13

Thrombotic microangiopathy (TMA) refers to conditions that cause microvascular thrombosis and result in microangiopathic haemolytic anaemia with presence of fragmented red cells on peripheral blood, thrombocytopenia and end organ damage. Syndromes most commonly associated with thrombotic microangiopathy are thrombotic thrombocytopenic purpura (TTP) and haemolytic uraemicsyndrome (HUS). TMA may occur in other disorders, such as malignant hypertension, scleroderma, systemic lupus erythematosus, preeclampsia, radiation nephropathy, renal allograft rejection, HIV infection, disseminated malignancies and disseminated intravascular coagulation (DIC). TTP is afatal thrombotic microangiopathy if not treated appropriately. Using a variety of approaches and case definitions the incidence of TTP has been estimated to be 2-7 per million person-years. The pentad of signs and symptoms of TTP include thrombocytopenia, microangiopathic haemolyticanaemia, neurological abnormalities, renal failure and fever.