Splenectomy, corticosteroids, and antiplatelet agents have improved survival in thrombotic thrombocytopenic purpura (TTP). In 1974 we reported the successful treatment in 5 of 6 patients using splenectomy, corticosteroids, and average molecular weight dextran. This report describes a 10-yr experience with TTP at Mount Sinai Hospital (MSH). Twenty patients with TTP were seen. Possible inciting factors included pregnancy, oral contraceptives, and surgery. Splenectomy was performed in 18 patients and typical findings of TTP were found in 14 (78%). Fifteen patients were treated with splenectomy, corticosteroids, and average molecular weight dextran. Two of the 15 patients received, in addition, ASA and dipyridamole and a third received only dipyridamole. Thirteen of the 15 (87%) have survived and remain disease-free.