Duodenal Diverticular Arteriovenous Malformation as a Cause for Gastrointestinal Bleed: A Report and Review of Literature

Abstract

Purpose: A 57-year-old Caucasian man presented to the emergency room with a tarry black stool and hemoglobin value of 9.8 gm/dL. He was advised endoscopy but refused. He returned 3 days later with continuing bleeding and a further drop in his hemoglobin value. He underwent esophagogastroduodenoscopy with forward viewing endoscope, which demonstrated fresh red blood in the third and fourth portions of the duodenum, but no obvious source for the bleeding. Push enteroscopy showed that red blood largely cleared by the mid-jejunum but again no source for bleeding could be seen. He was started on high dose proton pump inhibitor but continued to have melena with further drops in hemoglobin value. A tagged red blood scan failed to demonstrate a source for blood loss in the gastrointestinal (GI) tract. Computed Tomography of the abdomen was negative for any structural lesions, but suspicious for a descending duodenal diverticulum. He was re-evaluated with side-viewing endoscope, which demonstrated a single large peri-ampullary complex duodenal diverticulum which had been concealed from view of straight viewing endoscope by two overlapping adjacent folds. Further exploration of the complex diverticulum demonstrated a bleeding arteriovenous malformation (AVM) which was successfully cauterized with a gold probe (2.3mm/ 7 French, Boston Scientific Product No M00560070) with resolution of melena. The majority of duodenal diverticulae are asymptomatic, but may be complicated by obstruction, perforation or hemorrhage. The incidence of hemorrhage from duodenal diverticulae is unknown, but rare. Causes for bleeding duodenal diverticulae include erosion into arterial vessels, Dieulafoy lesions in the diverticulum, and bleeding intra-diverticular polyps. Also, ectopic gastric mucosa or impacted food may contribute to ulceration of duodenal diverticula. Our review of the literature indicated that bleeding from duodenal diverticular AVMs are exceedingly rare. To the best of our knowledge, only 2 previous cases of gastrointestinal hemorrhage from duodenal diverticular AVMs have been reported: one was visually confirmed at the time of standard endoscopy and the other was discovered during surgery. In instances where repeat endoscopy and push enteroscopy fail to isolate a cause for upper GI bleed, side view endoscopy can potentially yield a diagnosis more expediently and efficaciously than capsule enteroscopy or angiography. We suggest incorporating into practice guidelines a role for side-view endoscopy in cases where blood is visualized in the duodenum without a clear source. The literature has demonstrated several instances where this quick, cost-effective procedure has yielded potentially life-saving results.