Treatment of resistant thrombotic thrombocytopenic purpura with rituximab and cyclophosphamide.

Thrombotic thrombocytopenic purpura (TTP) is an uncommon acquired disease in adults, especially young women, characterized by fever, neurologic manifestations, microangiopathic hemolytic anemia, thrombocytopenia, and renal dysfunction. Treatment with plasmapheresis has increased the survival rate from 10% to greater than 90%. Still, a subset of patients with resistant TTP fail to respond to plasmapheresis or remain dependent on this procedure. We report such a patient who was successfully treated with rituximab and cyclophosphamide. She has now been disease free for more than 6 months. This novel treatment modality for TTP has been described for only a few patients. A well-controlled clinical trial is warranted to determine the role and place of this therapeutic approach in the management of TTP.