Low-dose rituximab for the treatment of acute thrombotic thrombocytopenic purpura: report of four cases.

Objective And Importance: Thrombotic thrombocytopenic purpura (TTP) is a life-threatening disorder that needs prompt diagnosis and treatment. Front-line therapy consists of plasma exchange (PEx) and steroids, but, in some instances, this is not enough to achieve a complete and sustained response.

Clinical Presentation: We report four cases of TTP treated with low-dose rituximab, PEx, and a short course of steroids with an excellent outcome. Three of the patients had primary TTP and another presented an underlying human immunodeficiency virus infection.

Intervention: Rituximab, 100 mg intravenously, was initiated on days 2-8 from the start of PEx as first-line therapy in three cases and as salvage therapy for relapsing disease in one. The number of PEx needed ranged from 5 to 12 sessions. All patients achieved complete remission and are currently asymptomatic, with complete response duration of 8-22 months.

Conclusion: Treatment of TTP with low-dose rituximab, along with PEx and steroids, seems to be as effective as the standard dose of monoclonal antibody.