Delayed Diagnosis of a Giant Abdominal Aortic Aneurysm Complicating to Aortoenteric Fistula: A Case Report and Literature Review.

A 53-year-old man with chronic back pain and systemic symptoms was diagnosed with a massive abdominal aortic aneurysm (AAA) and aortoenteric fistula (AEF), which can cause severe gastrointestinal bleeding and potentially fatal side effects. In patients with chronic back pain and systemic symptoms, this case emphasizes the value of early imaging and a high level of clinical suspicion for AAA. AEF and rupture are two major consequences of a delayed diagnosis. Improving results in such complicated vascular presentations requires prompt management and careful postoperative surveillance. The case highlights the importance of early imaging and clinical suspicion for AAA, as delayed diagnosis can lead to complications like AEF and rupture.