INFECTED ANEURYSMS OF THE INFRARENAL ABDOMINAL-AORTA - DIAGNOSTIC-CRITERIA AND THERAPEUTIC STRATEGY

From 1976 to 1994 we performed surgical treatment of 18 infected aneur ysms of the infrarenal abdominal aorta. The aneurysm had ruptured in n ine patients: into the retroperitoneum in six patients, and into an ad jacent structure in three patients (duodenum, inferior vena cava, left renal vein). Two patients had an associated spondylitis. Four patient s were in shock at the time of surgical treatment. Six patients (inclu ding four patients with Salmonella infection and two patients with spo ndylitis) had positive preoperative blood cultures. Salmonella was the most common microorganism (27%). Anaerobes accounted for 16%. In situ replacement was performed in 13 patients including three procedures p erformed under emergency conditions with frank purulent infection. Ext raanatomic bypass was performed in five patients. Early postoperative death occurred in two patients (11%) due to septic complications (rupt ure of aortic anastomosis in one patient and rupture of aortic stump i n one patient). All surviving patients underwent prolonged antibiotic therapy for at least 6 weeks. Overall mortality secondary to infected aneurysm was 16%. Infection of the aortic graft occurred in four patie nts (38%) including two patients with Salmonella infection and one pat ient with spondylitis. One patient developed a false anastomotic aneur ysm 6 months postoperatively and was treated by in situ arterial allog raft replacement. Postoperative blood cultures were positive in two pa tients presenting spondylitis and infection of the aortic prosthesis o ccurred in one of these patients. In addition to rupture, poor prognos tic factors included spondylitis and Salmonella infection that were fo und to greatly enhance the risk of postoperative graft infection follo wing in situ reconstruction.