Treatment of thrombotic thrombocytopenic purpura. Evaluation of plasma exchange and review of the literature.

: This report examines the results of treatment in 21 patients with thrombotic thrombocytopenic purpura (TTP) diagnosed over a 4-year time period (1976-1980) with a review of the possible role of each form of therapy in relationship to the various proposed pathogenic mechanisms. There was a 76.2% (16/21) overall survival with no significant difference in initial hematologic values in patients not surviving. Patients not surviving did not achieve a sustained platelet count greater than 150,000/microliters at any time during their clinical course. 16 patients received steroids, antiplatelet agents and plasma exchange, with a total volume exchanged ranging from 20.8 to 1,455 ml/kg, as part of their treatment protocol. In this group of patients there was an 81.2% (13/16) survival, with 4 patients receiving additional therapy including splenectomy and/or vincristine. There was no correlation between the intensity of plasma exchange and the time to hematologic recovery. It is apparent that controlled clinical trials are necessary to better define the effectiveness of the present forms of therapy.