Diagnosis of an Occult Aortoenteric Fistula and Treatment of a Silent Threat.

An aortoenteric fistula (AEF) is an abnormal communication between the aorta and the gastrointestinal tract, which can lead to severe gastrointestinal bleeding, sepsis, and high mortality if not promptly diagnosed and surgically managed. Its occurrence, particularly in patients with prior aortic surgery, presents considerable diagnostic and therapeutic challenges. This case report describes an iatrogenic aorto-duodenal fistula following surgical intervention at the aortoiliac bifurcation, highlighting the complexity and rarity of this entity. The clinical presentation of AEF is often insidious, delaying diagnosis. While no imaging modality provides definitive confirmation, computed tomography (CT) remains the most effective and widely utilized tool for detection. Key imaging findings in patients presenting with gastrointestinal bleeding include contrast extravasation from the aorta into the intestinal lumen, as well as the presence of enteric material or gas within the periprosthetic space. Early recognition of these radiologic indicators is critical to timely intervention. Surgical repair remains the mainstay of treatment, with the primary objectives being hemostasis, aortic reconstruction, and infection control. The choice of surgical approach is dictated by the location and extent of the fistula, as well as the patient's overall clinical status. Despite advancements in imaging and surgical techniques, AEF continues to pose a major diagnostic and therapeutic challenge. A high index of suspicion and familiarity with its clinical and radiologic presentation are essential for early recognition and optimal management.