Roles of endovascular aneurysm repair in management of secondary aorto-enteric fistulas

A Case of Problem-Free Survival Five Years After Abdominal Aortic Sigmoid Colon Fistula Surgery

An aortoenteric fistula (AEF) is a rare but life-threatening condition where an abnormal connection forms between the aorta and the gastrointestinal tract, most commonly the duodenum. It can be primary (arising spontaneously due to an aortic aneurysm or infection) or secondary (complicating prior vascular surgery). Immediate recognition and surgical intervention are critical to manage severe gastrointestinal bleeding and prevent fatal outcomes. A 71-year-old male developed an AEF following abdominal aortic graft surgery. Four months postoperatively, he presented with persistent lower gastrointestinal bleeding and was diagnosed with a secondary AEF. A staged surgical approach was employed, involving initial bowel resection, stoma creation, and graft cleaning, followed by subsequent aortic graft replacement with omental flap coverage. Postoperatively, a graft rupture at the proximal anastomosis required emergency endovascular stenting, which stabilized the patient. Antibiotic therapy successfully managed graft infection, including meropenem, linezolid, and later levofloxacin. The patient was discharged home on day 65 and has remained free of aortic events for five years. This case illustrates the complexity of AEF management, emphasizing the importance of a multidisciplinary, staged approach to achieve infection control, hemostasis, and long-term stability. He has been followed up in an outpatient clinic since then. He is now 76 years old, five years later, and is progressing without an aortic event.

Primary aortoenteric fistula: A case report and brief review of the literature

Aortoenteric fistula is a life-threatening emergency and is associated with high morbidity and mortality. Prompt surgical intervention before the aneurysm ruptures lowers the mortality rate to about 50%. Potential imaging mimics for aortoenteric fistula include retroperitoneal fibrosis, mycotic aortic aneurysm, and infectious aortitis. Secondary aortoenteric fistula has relative higher incidence compared to primary and is more common with open aortic repair versus endovascular stent graft repair. Ectopic gas in the aneurysm sac and extravasation of enteric contrast into the aneurysm sac is diagnostic for aortoenteric fistula. However, enteric contrast is not recommended for routine evaluation of aortoenteric because the aforementioned finding is extremely rare. More common imaging findings include bowel loop appearing adherent to aneurysm sac with associated inflammatory stranding and foci or ectopic gas within the aneurysm sac or interposed between the bowel and aneurysm sac. Here we present a case of 52-year-old male who presents with incidental primary aortoenteric fistula.