Abdominal aortic aneurysms infected by Escherichia coli.

Three cases of atherosclerotic abdominal aneurysms infected by Escherichia coli urinary tract sepsis are presented together with a review of four additional cases of E. coli-infected aneurysms. Pathophysiology and a current system of classification of aortic infection are discussed. Important clinical features of gram-negative aortic infection include a diagnostic triad and the tendency to early rupture. Resection of infected tissue and extra-anatomic bypass for revascularization are the cornerstones of operative management. The mortality rate of E. coli aortic infection is high, with one known survivor. Death is contributed to by the high frequency of preoperative rupture, the age of the patient, and the extent of atherosclerotic disease.