• We evaluated the microbiologic nature of aneurysm contents. Aerobic and anaerobic cultures were taken from nonblood fluid, laminar thrombus, or ulcerated plaque within aortic aneurysms operated on during an eight-year period. Positive bacterial cultures were obtained from 22(10.4%) of 211 aneurysms. Staphylococcus epidermidis was the most common organism recovered (12/22, 54%). Bacterial colonization of the arterial wall has a possible role in the pathophysiology of prosthetic graft sepsis. These data are valuable not only in choosing appropriate prophylactic antibiotics for aneurysm repair, but also in experimental efforts to develop an infectionresistant vascular graft by directing the antimicrobial characteristics of agents selected for binding to various prosthetic flow surfaces.
(Arch Surg 1987;122:777-780)