Gastrointestinal tract involvement by prosthetic graft infection. The significance of gastrointestinal hemorrhage.

To investigate the patterns of interaction between vascular graft complications and the gastrointestinal (GI) tract, the incidence, pattern, and cause of GI bleeding among patients treated for secondary aortoenteric fistula (AEF) or chronic perigraft infection (PGI) was reviewed. Among 110 patients with infected grafts, there were 39 with secondary AEF and 71 chronic PGI. GI hemorrhage occurred in 24 AEF patients (61.5%), five PGI patients (9.4%) with aortoiliofemoral grafts (PGI-AIF), and in no PGI patients with peripherally located grafts (PGI-Other). The incidence of acute and chronic bleeding patterns was the same in both AEF and PGI patients. All GI bleeding in PGI patients was from the upper GI tract, whereas lower GI hemorrhage predominated slightly among AEF patients. Endoscopy was often negative among AEF patients (10 of 17) but always diagnosed the etiology of bleeding in PGI patients (gastritis in four; duodenal ulcer in one). Fifteen AEF patients (38%) had no evidence of GI bleeding at any time during evaluation. Acute hemorrhage among AEF patients was usually associated with an anastomotic fistula (10 of 14), while paraprosthetic fistulas often did not bleed (6 of 10) or bled chronically (12 of 15). Sepsis occurred significantly more often among AEF patients (8 of 39, 21%) than among PGI patients (2 of 71, 3.0%). However, there was no significant difference in the incidence of sepsis or systemic infection between PGI-AIF patients and PGI-Other patients. In summary, gastrointestinal involvement by prosthetic graft infection may be either direct (fistula formation), indirect (sepsis/infection induced stress gastritis or ulceration), or silent. No absolute correlation exists between GI hemorrhage and the presence or absence of a graft-enteric fistula. Endoscopic demonstration of nonfistula GI pathology does not exclude the presence of graft infection. Recognition of these patterns of GI tract involvement by vascular graft infection may facilitate prompt diagnosis and improve treatment results.