Small arteriovenous malformation of the common bile duct causing hemobilia in a patient with hereditary hemorrhagic telangiectasia.

We report a 54-year-old male patient with arteriovenous malformation located at the common bile duct and hereditary hemorrhagic telangiectasia. The patient was treated as gallstone pancreatitis at first. Three days after endoscopic nasobiliary drainage (ENBD) for biliary drainage to subside gallstone pancreatitis, hemobilia was drained from the ENBD tube and the serum hemoglobin level gradually decreased. Cholangioscopy and angiography revealed that hemobilia was due to a small arteriovenous malformation located at the common bile duct. Subsequently, the patient was successfully treated by endovascular intervention.