Aortoenteric fistula secondary to an Inflammatory Abdominal Aortic Aneurysm


  • Shuhui Melissa Lee
  • Yusheng Keefe Lai
  • Wei David Wen



Aortoenteric fistula, primary, secondary, inflammatory abdominal aortic aneurysm, mycotic aneurysm, infectious aortitis, CT, MRI, ultrasound, radiotracer, abdomen


Primary aortoenteric fistulas are rare, with the annual incidence of such fistulas estimated to be 0.007 per million. The most common predisposing conditions for primary aortoenteric fistulas are atherosclerotic abdominal aortic aneurysms or penetrating atherosclerotic ulcers. We illustrate a rare case of an inflammatory aortic aneurysm causing a primary aortic fistula, with a direct fistulous jet from the aorta to the bowel with resultant catastrophic bleeding. In contrast to atherosclerotic aneurysms, most inflammatory aneurysms are symptomatic and show dense perianeurysmal fibrosis and periaortic wall thickening. A direct jet of contrast extravasation from the aorta into a bowel loop, while rarely seen, remains the most specific sign of a primary aorta-enteric fistula. A comprehensive literature review of the clinical presentation, imaging features, and differential diagnosis of a primary aortoenteric fistula are also discussed.

Author Biographies

Shuhui Melissa Lee

Department of Diagnostic Radiology, Singapore General Hospital, Singapore

Senior Resident

Yusheng Keefe Lai

Department of Diagnostic Radiology, Singapore General Hospital, Singapore

Associate Consultant

Wei David Wen

Department of Diagnostic Radiology,

Singapore General Hospital

Associate Consultant





Gastrointestinal Radiology