S1646 THE COMBINATION OF LOW ADAMTS-13 ACTIVITY AND HIGH ANTI-ADAMTS13 ANTIBODIES AT REMISSION HIGHLY PREDICTS DISEASE RELAPSE IN PATIENTS WITH ACQUIRED TTP: A MULTI-INSTITUTIONAL STUDY

Background: Acquired thrombotic thrombocytopenic purpura (aTTP) is an immune-mediated life-threatening thrombotic microangiopathy (TMA). Daily therapeutic plasma exchange (TPE) and the optimized use of rituximab have dramatically improved the overall prognosis, however the rate of disease recurrence remains high. Acute-phase treatment and specific predictors of relapse can be relevant for an optimal patient management. Aims: In a large...