Computed tomographic scan confirmation of paraprosthetic enteric fistula.

Aortoenteric anastomotic fistulae and paraprosthetic graft infections are rare but devastating complications following aortic graft surgery. Although the incidence of these complications is reported to be less than 2%, the difficulty in diagnosis and management has led to high mortality rates and extensive morbidity. The majority of patients present with either groin infection or significant gastrointestinal tract bleeding. There is, however, a subset of patients with nonspecific clinical findings in whom routine studies are not diagnostic. Computed tomography was a useful adjunct to the diagnosis of retroperitoneal infection in these patients by demonstrating small collections of periaortic gas or "black dots." The presence of periaortic gas in each instance proved to be a specific sign of a paraprosthetic-enteric fistula, as opposed to a graft infection without intestinal communication.