Aortoenteric Fistula Masquerading as Intermittent GI Bleeding

Abstract

SESSION TITLE: Critical Care 2 SESSION TYPE: Affiliate Case Report Poster PRESENTED ON: Tuesday, October 31, 2017 at 01:30 PM - 02:30 PM INTRODUCTION: Secondary aortoenteric fistula usually occurs in patients with AAA repair, with an incidence of 0.4-3.1%. It is a life-threatening complication, with a mortality rate of 100% if left untreated. CASE PRESENTATION: A 77 y/o male presented with 2 L of bloody bowel movement. He had an AAA repair five years ago. His vitals and physical examination were unremarkable. However, his haemoglobin dropped from 12.5 mg/dL to 11.8 mg/dL. CT abdomen with contrast showed recto-sigmoid diverticulosis and a stable surgical aortic graft. Colonoscopy revealed diverticulosis in sigmoid colon. Over the next 7 days, he had intermittent episodes of large bloody bowel movements, during which haemoglobin decreased to 6-7 mg/dL and he was transfused. Angiogram and tagged red blood cell scan were negative. On the 7th day, he had abdominal pain with large bloody bowel movement. EGD revealed a defect on the posterior wall of the proximal jejunum, extruding a continuous high-pressure jet of blood, which represented a possibility of an aortoenteric fistula. He remained stable for the next two days. Then he developed hypotension and was started on vasopressors. A repeat EGD at this time did not show a bleeding source in the jejunum. He underwent explorative laparotomy, which showed the proximal small bowel plastered to the aortic graft with a questionable ulcer in the jejunum. No aortoenteric fistula was found. No intervention was undertaken. Subsequently, in the next few days he developed abdominal pain and then lost consciousness. He underwent emergent laparotomy that revealed an intraperitoneal haemorrhage from the distal aspect of the aortic graft anastomosis, which was opposed to the jejunum previously. The bleeding from the aorta was controlled and the bowel defect was fixed with an omental patch. Post-op the patient was stable. DISCUSSION: Secondary aortoenteric fistulas mostly occur after AAA repair, mostly at a site proximal to the aortic graft; or graft infection. In intermittent GI bleeding, a thorough history, physical examination along with imaging is useful in >90% of cases. Endoscopy and push enteroscopy have a more diagnostic yield. Definite treatment is open surgical repair or endovascular stent placement. CONCLUSIONS: In patients with a history of aortic repair presenting with intermittent GI bleeding, aortoenteric fistulas should be high on the differential diagnosis, since delay or missed diagnosis can lead to mortality. Reference #1: Marlot, U et al. “Aortoduodenal fistula three years after aortobifemoral bypass: case report and literature review.” Acta Clin Croat. 52.3(2013): 363-368. Reference #2: Senadhi, V et al. “A Mysterious Cause of Gastrointestinal Bleeding Disguising Itself as Diverticulosis and Peptic Ulcer Disease.” Case Rep Gastroenterol. 4.3(2010): 510-517. Reference #3: Yazdanpanah, K., and Mohammad Minakari. “Intermittent Herald Bleeding: An Alarm for Prevention of the Exsanguination of Aortoenteric Fistula before it Arrives.” Int J Prev Med. 3.11(2012): 815-816. DISCLOSURE: The following authors have nothing to disclose: Sidra Khalid, Jyothirmai Seepana, Narendrakumar Alappan No Product/Research Disclosure Information