Hemodialysis-exchange transfusion for treatment of thrombotic thrombocytopenic purpura.

Remission in thrombotic thrombocytopenic purpura (TTP) was achieved in two patients after repeated exchange transfusion. Since both patients had renal insufficiency, exchange was performed with hemodialysis. This provided optimal volume control and facilitated the rapid exchange of blood. The infusion of plasma did not maintain the clinical improvement achieved with exchange transfusion. Until a concentrate of the putative factor deficient in TTP becomes available, an exchange procedure remains the most expeditious method for the replacement of any deficient factor. The procedure of hemodialysis can be adapted to perform exchange transfusion safely and efficiently.