Two patients with thrombotic thrombocytopenic purpura (TTP) were treated with a combination of antiplatelet drugs, corticosteroids, and plasma exchange. There was immediate clinical and laboratory improvement in both patients. However, the improvement did not persist following plasma exchange, even with infusions of fresh frozen plasma. Splenectomy was performed on both patients with subsequent sustained remission of the disease. Platelet counts returned to normal within eight days (case 1) and five days (case 2). Follow-up at eight months in one patient and at four months in the other disclosed normal laboratory values with no evidence of recurrent TTP. These cases suggest that in addition to other therapies, splenectomy may be beneficial in some patients.