Primary aortoduodenal fistula: manifestation, diagnosis, and treatment.

Primary aortoduodenal fistulas are an especially lethal part of the spectrum of arterioenteric fistulas. The lethal nature is due to the subtleties in manifestation, leading to delays in diagnosis and institution of prompt operative repair. A review of the 118 primary aortoduodenal fistulas in the world's literature reveals that pain (32%), palpable abdominal mass (25%), and bleeding (64%) are inconsistently present as initial symptoms and that routine abdominal films, barium studies, and endoscopy have been ineffective as diagnostic aids. Attention is called to the importance of recognizing the "herald bleed." Operation is usually undertaken emergently and has been successful in only 21 cases in addition to the case reported here. Repair of the duodenal rent and replacement of the aorta with a Dacron prosthesis, rather than an extra-anatomic bypass, is advised.