RESUMO
BACKGROUND: Acquired thrombotic thrombocytopenic purpura (TTP) is caused by a deficiency of von Willebrand factor-cleaving protease (ADAMTS13) and is often associated with the presence of an antibody inhibiting the activity of the protease. Typically, 1-1.5 plasma volume exchanges are performed daily until symptoms have resolved and the platelet count exceeds 150,000/µl. Plasma is the usual replacement fluid as it provides a source of functional ADAMTS13, thus exposing patients to large volumes of plasma. Historically, Puget Sound Blood Center (PSBC) has performed therapeutic plasma exchange (TPEs) for TTP using 5% albumin for the first half of the procedure followed by plasma for the remainder. We sought to assess the efficacy of this approach. STUDY DESIGN AND METHODS: All TPEs performed for the diagnosis of TTP by the PSBC apheresis service from January 1, 2004 through December 31, 2011 were reviewed. Response time, remission rates, relapses, and adverse events were evaluated for those patients with documented ADAMTS13 levels ≤10%. Comparisons were made with published data on TTP patients treated using 100% plasma replacement. RESULTS: Twenty-one patients required a median of 11 TPEs. Median time to response was 14 days. Ninety percent of patients responded to TPE. Among patients achieving remission, 53% relapsed. Out of 283 total procedures, there were 74 procedures with a documented adverse event (26%), mostly mild allergic reactions. CONCLUSIONS: TPE with an albumin/plasma replacement is safe and well-tolerated. Remission and relapse rates were comparable to those reported using 100% plasma replacement.