[Thrombotic-thrombocytopenic purpura].

Thrombotic-thrombocytopenic purpura (TTP) is a microangiopathic disorder characterized by multiple von Willebrand-Factor (vWF) rich microthrombi affecting the arterioles and capillary vessels of several organs. Ultra large von Willebrand multimers cause the blood clotting process by linking to platelets due to a lack of a plasma metalloprotease named ADAMTS13. Deficiency of this vWF-cleaving enzyme is caused by an inborn mutation in the gene coding or, more often, by acquired autoantibodies that inhibit ADAMTS13. TTP is a life-threatening disease which requires urgent admission to a hematological centre. Plasmapheresis therapy should be started immediately when diagnosis of primary TTP is likely. Patients typically present with schistozytes, hemolysis, thrombocytopenia and neurological abnormalities such as headache, focal deficits or coma. The monoclonal CD20 antibody rituximab targets ADAMTS13 antibody production and has the potential to be an effective therapy for relapsed TTP or initial treatment to shorten duration of plasma exchange.