A 49-year-old woman presented to the emergency department with bright red rectal bleeding, a hemoglobin level of 8.6 g/dL, and a hematocrit level of 27.8%. Because of complications of type 1 diabetes mellitus, the patient received a pancreaticoduodenal transplant with ileum drainage 8 years before presentation. This allograft failed 5 months before presentation, presumably owing to rejection. Bleeding necessitated nearly continuous high-volume fluid resuscitation. Results of angiography revealed perfusion of the pancreatic allograft (panel A, arrow) and extravasation of contrast material into the small bowel (panel B, arrow; imaged obtained a few seconds later). Interventional radiologic and vascular surgery services were not available. Despite heroic measures that included Fogarty catheter placement in the allograft arterial pedicle, the patient died of exsanguination. In a 14-hour period, she received 24 U of packed red blood cells, 22 U of fresh frozen plasma, other blood products, and crystalloids. The present case illustrates the potentially devastating complication of an arterioenteric fistula after an enteric-drained pancreaticoduodenal transplant, which has also been noted in other cases.^1-4