Recent therapeutic advances in thrombotic thrombocytopenic purpura.

Whole plasma infusion, in our experience, has been highly effective in the management of patients with thrombotic thrombocytopenic purpura. The effectiveness of plasma infusion in the treatment of this severe disorder implies the deficiency of a factor in the patient's plasma. Furthermore, we have observed that when platelets are suspended in plasma obtained during active, untreated thrombotic purpura, aggregation occurs. This effect is neutralized by preincubation of the thrombotic thrombocytopenic purpura plasma with normal plasma. Thus, there is both a correlation with the clinical pathogenic mechanism, disseminated platelet aggregation, and with the therapeutic response to plasma infusion. Based upon our experience and the concept that thrombotic thrombocytopenic purpura is a plasma factor deficiency state, we recommend initial infusion of a full plasma volume equivalent over the first 24 hours. This should be done under an intensive care setting. After this initial plasma infusion, we advise the infusion of 3 units of plasma daily until a full remission is obtained. When the clinical situation has stabilized, we stop the daily plasma infusions and cautiously observe for recurrence of the manifestations of thrombotic thrombocytopenic purpura. If there is a recurrence, plasma is again infused in substantial quantity during the first 24 hours and then 3 units daily until a full remission is again evident. Whether the plasma requirement might be attenuated or the course of the disease shortened by the concomitant use of antiplatelet agents, corticosteroids or other means remains to be determined.