Haematemesis due to primary aortic aneurysm-duodenal fistula - clinical suspicion is the cornerstone of diagnosis: a case report

INTRODUCTION: Although gastrointestinal haemorrhage from aortoduodenal fistulae secondary to previous aortic grafts are well known, a primary fistula from an aortic aneurysm is a rare consideration resulting in inappropriate management and poor outcomes. CASE PRESENTATION: We report a previously fit 65-year-old Sri Lankan man who presented with severe anaemia (haemoglobin, 6 gm/dl), recent onset low backache. There was no history of analgesic abuse, peptic ulceration, alcohol excess, weight loss or malena. The abdomen was soft and there was no visceromegaly. A routine ultrasound detected an abdominal aortic aneurysm without signs of a leak. Two days later, while undergoing routine diagnostic tests for anaemia and backache, he had a massive haematemesis. Standard resuscitation was commenced with hope that common sources, either peptic ulcers or varicies would eventually stop bleeding enabling endoscopy and definitive treatment. However, persistent hypotension coupled with the clinical suspicion of an aortoduodenal fistula led to immediate surgical exploration rather than continued aggressive resuscitation. An aortoduodenal fistula was confirmed and both the duodenum and the aorta were successfully repaired by direct suture and synthetic graft replacement respectively. This man remains well nine months later. CONCLUSION: Gastrointestinal bleeding in the presence of an ‘asymptomatic’ abdominal aortic aneurysms should be assumed to be from a primary aortoduodenal fistula unless another source can be identified with certainty without delay.