A bleeding tendency as the first symptom of a choledochal cyst.

We report an 8-month-old male presenting with gingival hemorrhages and nasal bleeding as the first symptom of a choledochal cyst (CC). On physical examination, there was a large cystic mass in the right upper abdominal quadrant. Laboratory studies on admission revealed moderate liver dysfunction and a bleeding tendency due to vitamin K deficiency. After administration of 5 mg vitamin K the bleeding tendency disappeared. At laparotomy, a large CC 5 cm in diameter was found and the liver showed moderate cholestasis. The sudden onset of a bleeding tendency in infants with congenital liver or biliary-tract disease may suggest not only biliary atresia, but also CC.