Iloprost in the treatment of thrombotic microangiopathy: report of thirteen cases.

Defective prostacyclin bioavailability seems to play a role in the pathogenesis of thrombotic microangiopathy, including thrombotic thrombocytopenic purpura and hemolytic uremic syndrome. Eight consecutive patients with a proven diagnosis of thrombotic microangiopathy were treated by Iloprost, a recently developed stable prostacyclin analogue; during follow-up, three of them relapsed and received further treatment. To our knowledge, this is the first report on a wide series of patients who received Iloprost for thrombotic microangiopathy. Soon after diagnosis, Iloprost was given by continuous intravenous infusion at a rate of 1.5-2 ng/kg/minute over 16-18 h/day for several days (mean 12 days; range 6-24) until the platelet count steadily increased. In addition, plasma exchange with fresh frozen plasma (average volume exchange 20-40 mL/kg for each session) was performed in 11 out of the 13 cases. No other antiplatelet agent was given. In all 13 cases, Iloprost administration coincided with achievement of remission. At present, all the patients are still maintaining remission. Our results indicate a useful role for Iloprost in the management of thrombotic microangiopathy.