[Thrombotic thrombocytopenic purpura (TTP) in which plasmapheresis was ineffective but vincristine slow infusion therapy was effective with long-term remission].

A 38-year old female patient with thrombotic thrombocytopenic purpura (TTP) did not respond to plasmapheresis and treatment with corticosteroids and antiplatelet agents but did respond to subsequent high-dose gamma-globulin therapy and vincristine slow infusion therapy. Remission, thought to be due to vincristine, was achieved. The administration schedule of vincristine was 1 or 2 mg once a week by intravenous drip infusion over a period of 6 to 8 hr. Improvement tended to be seen after the 6th administration, and remission was achieved after the 12th administration (total dose: 15 mg), and continues to the time of this writing. In this case, it was thought that vincristine inhibited a certain excessive reaction in the process of PAIgG-related platelet consumption. We conclude that vincristine should be administered at least 5 to 6 times, and the therapeutic method should be established based on the experience in a larger number of clinical cases.