Background: This study was designed to assess the response of patients with thrombotic thrombocytopenic purpura to plasma exchange and to evaluate the role of splenectomy after relapse.
Methods: The records of all patients with thrombotic thrombocytopenic purpura who had plasma exchange as primary treatment at a single center during a 10-year period were retrospectively reviewed. Response to the initial course of plasma exchange was determined, and the clinical outcome was evaluated in patients whose conditions were either refractory to exchange, responded without relapse, or relapsed after initial response. The outcome of patients treated during relapse with splenectomy was evaluated. A literature review was conducted to determine the clinical outcome in patients treated similarly.
Results: Twenty-seven patients for whom data could be evaluated had been treated in the 10-year period. Twenty-one (78%) responded to the plasma exchange, but the conditions of six (22%) were refractory and these patients died. Eight patients (30%) had one or multiple relapses after initial response but had prolonged remissions after additional plasma exchange alone (two patients) or splenectomy (six patients). A review of 19 reports, including 224 patients with thrombotic thrombocytopenic purpura initially treated with plasma exchange, revealed similar findings, with initial response in 81%, refractoriness in 19%, and relapse after initial response in 27% of patients.
Conclusion: Response to plasma exchange in thrombotic thrombocytopenic purpura is associated with an excellent prognosis, and most deaths occur in patients whose conditions are refractory. Relapses after initial response are frequent but can be managed successfully with additional plasma exchange or with splenectomy, which often induces long-term remissions.