Plasmapheresis in thrombotic thrombocytopenic purpura.

Two patients with thrombotic thrombocytopenic purpura (TTP) were treated with plasmapheresis procedures in which the replacement fluid included normal plasma. In both cases, the platelet count rose, hemolysis decreased, and neurologic symptoms improved promptly after this therapy. Unfortunately, both patients eventually died, one of complications of end-organ damage and the other of complications of maintenance therapy with prednisone. Plasmapheresis may be an effective treatment for TTP, either by removing a toxic factor or supplying a deficient factor.