Thrombotic thrombocytopenic purpura with a subacute course: remission after steroids and high-dose plasma exchange.

: A case of thrombotic thrombocytopenic purpura with an unusual subacute course is described. Treatment was initiated after the patient had been ill for four weeks. Low-dose plasma exchange (10 ml/kg body weight per day) was associated with a sharp drop in the reticulocyte count and a transient reduction of lactate dehydrogenase activity to within the normal range. The administration of corticosteroids was followed immediately by the disappearance of neurological symptoms, and after high-dose plasma exchange (25 ml/kg body weight per day) all the symptoms of disease remitted. The remission has lasted for 10 months; we suggest that each of the therapeutic measures employed played a role.