1950 An Unexpectedly Large Vascular Anomaly Causing Chronic Obscure GI Hemorrhage: A Case Report

Abstract

INTRODUCTION: Approximately 5–10% of patients who present with an acute gastrointestinal (GI) hemorrhage have a primary small bowel source. While small bowel angioectasias are one of the most common causes of small bowel hemorrhage, it is rare to find large vascular anomalies in the small bowel as a cause of chronic GI bleed. CASE DESCRIPTION/METHODS: We present a case of a 56-year-old woman referred to our institution for management of obscure GI bleeding, associated with severe iron deficiency anemia. She had intermittent melena and occasional dark red blood mixed with stool. Extensive work up in an outside facility including 2 endoscopies, 2 colonoscopies, and a capsule endoscopy were unrevealing. After referral to our institution; push enteroscopy, colonoscopy and retrograde single balloon enteroscopy were performed and were negative for source of bleeding. Capsule endoscopy revealed a small oozing angioectasia in proximal jejunum. The lesion was treated with heater probe via anterograde single-balloon enteroscopy. Due to persistent melena and anemia, antegrade balloon enteroscopy was repeated and demonstrated an abnormal cluster of vascular-appearing lesions in the proximal jejunum that were marked with two hemostatic clips. CT angiogram was consistent with a large arteriovenous malformation (AVM). Interventional radiology performed glue embolization of the high-flow jejunal arteriovenous malformation. The post procedure course was complicated by ischemic proximal jejunum which was confirmed on repeat enteroscopy. Fortunately, her symptoms completely resolved with conservative management without surgical intervention. DISCUSSION: AVMs are abnormal lesions with a direct connection between the arterial and venous blood supply without any true capillary bed connecting them. While extremely rare within the GI tract, they can cause significant amount of bleeding and must be considered in patients with obscure GI bleeding or chronic iron deficiency anemia. Studies have shown that AVMs typically only account for 1–2% of upper GI bleeds. More common sites for AVMs include the cecum and ascending colon, while other sites like the small bowel are much more rare. Diagnostic work up typically begins with upper endoscopy followed by colonoscopy. However, these tests are often unrevealing when dealing with small bowel AVMs. Patient’s typically undergo capsule endoscopy for further evaluation, as seen in our patient. If the source of bleeding is still un-identified, then angiography or bleeding scans may be required.