Management of thrombotic thrombocytopenic purpura: current perspectives

Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening thrombotic microangiopathy which causes significant morbidity and mortality unless promptly recognized and treated. The underlying pathogenesis of TTP is a severe deficiency in ADAMTS13 activity, a metalloprotease that cleaves ultralarge von Willebrand factor multimers. This deficiency is either autoantibody mediated (acquired TTP) or due to deleterious mutations in the gene encoding ADAMTS13 (congenital TTP). The elucidation of this disease mechanism has reinforced the rationale and place of current therapies (eg, plasma exchange) as well as providing a basis for the prospective evaluation of immunotherapy with rituximab in addition to classic immunosuppression (eg, corticosteroid) in autoantibody-mediated TTP. This review discusses the current evidence base for therapeutic interventions in acquired and congenital TTP as well as providing a practical approach to the other aspects of investigation and management for which a firm evidence base is lacking. Novel agents that are currently being evaluated in prospective trials and future directions of therapy are also discussed which are expected to make an important contribution to improving outcomes in patients with TTP.