Arteriojejunal Fistula Presenting with Recurrent Obscure GI Hemorrhage in a Patient with a Failed Pancreas Allograft

We present a case of a patient with a failed pancreaticoduodenal allograft with exocrine enteric-drainage who developed catastrophic gastrointestinal (GI) hemorrhage. Over the course of a week, she presented with recurrent GI bleeds of obscure etiology. Multiple esophago-gastro-duodenoscopic (EGD) and colonoscopic evaluations failed to reveal the source of the hemorrhage. A capsule endoscopy and a technetium-labeled red blood cells (RBC) imaging study were similarly unrevealing for source of bleeding. She subsequently developed hemorrhagic shock requiring emergent superior mesenteric arteriography. Run off images revealed an external iliac artery aneurysm with fistulization into the jejunum. Coiled embolization was attempted but abandoned because of hemodynamic instability. Deployment of a covered endovascular stent into the right external iliac artery over the fistula site resulted in immediate hemodynamic stabilization. A high index of suspicion for arterioenteric fistulae is needed for diagnosis of this uncommon but eminently treatable form of GI hemorrhage in this patient population. 1. Introduction Simultaneous pancreas and kidney transplantation is the standard of care for type 1 diabetes mellitus (DM) with end-stage renal disease (ESRD) with an increased frequency of exocrine enteric drainage [1]. Common vascular complications after pancreas transplantation include venous and arterial thrombosis, vascular stenosis and kinks, and arterial dissection due to either clamping injuries or native atherosclerotic disease [2]. Uncommon vascular complications after pancreas transplantation include arteriovenous (AV) fistulae and pseudoaneurysms, arterioenteric (AE) fistulae, enteric anastomotic bleeding, and mycotic pseudoaneurysms [3–10]. AE and AV fistulae after failed pancreas allograft are challenging entities for obscure GI bleeding. Bleeding from these AE/AV fistulae can be extensive leading to increased morbidity and mortality [6, 7, 11]. The diagnosis of these vascular abnormalities is often perplexing, and a high index of suspicion is required in patients with previous abdominal operations or radiation who present with overt GI bleeding of uncertain etiology [12–15]. However, catastrophic bleeding in a critically ill patient with an AE/AV fistula following failed pancreas allograft needs urgent embolization and/or endovascular stent placement. We here present a rare case of failed deceased donor pancreas allograft (exocrine enteric drainage and systemic venous system drainage) with recurrent obscure GI bleeding. Ultimately, an external iliac