Successful management of pregnancy-associated thrombotic thrombocytopenic purpura by monitoring ADAMTS13 activity

Abstract

Thrombotic thrombocytopenic purpura (TTP) during pregnancy is very rare and is caused by an absent or severely depleted ADAMTS13 (a disintegrin-like and metallopeptidase with thrombospondin type 1 motif, 13). A 37-year-old multigravida woman developed TTP with severe anemia and thrombocytopenia at 22 weeks' gestation. ADAMTS13 activity was markedly decreased to 3% and ADAMTS13 inhibitor was positive, leading to a definitive diagnosis of TTP. She was successfully treated by plasmapheresis six times, resulting in symptomatic relief. Close follow up with periodic ADAMTS13 measurement facilitated plasmapheresis at appropriate points at a minimum frequency during pregnancy. Because of intrauterine growth retardation from 28 weeks' gestation, an elective cesarean section was performed at 30 weeks' gestation. After delivery, the mother and child showed no appreciable problem. To our knowledge, this is the first report of successful management for pregnancy-associated TTP by monitoring ADAMTS13 activity during pregnancy and the postpartum period.