Relapsing Thrombotic Thrombocytopenic Purpura with Low ADAMTS13 Antigen Levels: An Indication for Splenectomy?

With more recent modalities of immunosuppression, splenectomy is now rarely considered in refractory/relapsed thrombotic thrombocytopenic purpura (TTP). However, the surgical approach had shown convincing evidences of high efficacy in the pre-rituximab era and therefore may still represent a lifesaving option in selected challenging cases. To define the characteristics of subjects who may benefit from splenectomy may ease clinical decision making. In this paper we describe the clinical and laboratory data of 2 multiple relapsing TTP cases who successfully underwent splenectomy in the pre-rituximab era. Whereas high anti-ADAMTS13 antibody titre and low ADAMTS13 activity never correlated with remission and relapse, a drop in the ADAMTS13 antigen level was always associated with the acute phase, whereas levels consistently returned to normal following splenectomy, heralding long term remission. Splenectomy may therefore be considered in refractory TTP cases associated with increased ADAMTS13 antigen clearance, irrespective of persistence of inhibitory antibodies.