Pancreatic arteriovenous malformation observed to bleed from the bile duct and a duodenal ulcer: report of a case.

A 48-year-old man with recurrent episodes of biliary colic and subsequent pancreatitis was admitted to undergo a cholecystectomy. A gastroduodenal fiberscopic examination was performed because of massive melena on the seventh day after admission. It revealed a shallow ulcer on the posterior wall of a duodenal bulbus with rubor and an exposed vessel, which was clipped endoscopically to stop the bleeding. Further observations showed the papilla of Vater to be bleeding from the papilla. A contrast-enhanced abdominal computed tomography scan demonstrated a dilatation of the common bile duct and several dilated vasculatures around the portal vein, some of which drained into the portal vein. Based on the angiography findings, a diagnosis of arteriovenous malformation in the pancreas head was obtained and an embolization of the gastroduodenal artery was performed. Although the melena subsided, he underwent a pylorus-preserving pancreatoduodenectomy to prevent the recurrence of hemorrhaging. The histopathological findings of the bile duct revealed inflammatory cell infiltration and a detachment of the epithelium, except in a small part of the bile duct. A rupture of a damaged vessel inside the bile duct was observed, which was thought to be the cause of hemobilia. Sections of the pancreatic head demonstrated an inflammatory lesion with fibrosis and saponification as well as a large degree of arteriovenous anastomosis. The patient was discharged on the 35th day after the operation following an uneventful postoperative course.