Acquired Hypoprothrombinemia Lupus Anticoagulant Syndrome Developed in a Healthy Child

Abstract

We report a 3-year-old boy without any underlying diseases who was diagnosed as having acquired hypoprothrombinemia lupus anticoagulant (LA) syndrome. He was admitted for evaluating a sudden onset of severe epistaxis and subcutaneous bleeding on buttocks and lower extremities 10 days after gastroenteritis. Platelet counts were normal, but PT and APTT were markedly prolonged (39.0 and 127.3 sec, respectively). PIVKA II was negative. Mixing test normalized PT, but not APTT. Coagulation studies revealed a low Factor II activity (10%) and a high titer of LA (2.19 of dRVVT/RVVT). Bleeding tendency and abnormal coagulation time became normal without any specific medications.