Primary aortoenteric fistula: report of eight new cases and review of the literature.

Primary aortoenteric fistula, a direct communication between the aorta and the intestinal tract, is a rare cause of gastrointestinal hemorrhage. Eight patients who were all treated at one hospital are described, followed by a review of all surgically treated patients reported within the past 10 years. The usual cause is erosion of an atherosclerotic aneurysm into the adherent duodenum, but a wide variety of other causes and localizations have been described. The clinical presentation is usually one of intermittent gastrointestinal hemorrhage resulting in lethal exsanguination within a matter of hours or days. Pain, a pulsatile abdominal mass, or fever may not be present. Endoscopy, arteriography, ultrasound, and CT scan can be useful in the evaluation of these patients, but physical examination and a high index of suspicion remain key to diagnosis. Primary aortoenteric fistula is more often discovered unexpectedly during exploratory laparotomy and is not usually considered as a presumptive preoperative diagnosis. Although contamination is unavoidable, most patients are treated with an in situ vascular graft and primary closure of the intestinal defect with good results.