Imaging work-up and endovascular treatment options for aorto-enteric fistula

Aorto-enteric fistula (AEF) is a rare though life-threatening condition that is formed when the aorta erodes through the wall of an adjacent segment of the gastrointestinal (GI) tract, leading to sepsis or hemorrhage if untreated. The current management of AEFs remains controversial. AEFs are traditionally classified as either primary or secondary, with the majority attributed to the latter category (1). Primary AEFs can occur as a direct consequence of large untreated descending thoracic or abdominal aortic aneurysms (AAAs) with or without associated infection (mycotic aneurysm or aortitis), eroding through the bowel wall, or due to bulky para-aortic tumoral tissue invading through the aortic wall. Secondary AEFs (SAEFs) are more common than primary AEFs and generally develop as a result of long-term sequelae of either surgical or endovascular aortic reconstruction, with no significant difference in SAEF incidence between the two approaches (2). Most AEFs develop between the duodenum and the aorta; however, they can occur in almost any section of the GI tract (3)