Mycotic abdominal aneurysm requiring emergency operation due to sudden thrombotic obstruction: a case report

A 59-year-old man was admitted with history of low grade fever, general malaise and low back pain. Physical examination showed a pulsatile mass in the mid-abdomen. There were slight leucocytosis, elevated BSR and CRP. Abdominal ultrasonography, CT and MRI revealed an abdominal aneurysm within which there was an intimal flap and thrombus. Though blood culture was not positive, antibiotic therapy was initiated on the presumption of a mycotic abdominal aneurysm. Six days after admission, he complained of numbness in the lower extremities and both femoral pulsations were not palpable. Emergency surgery was undertaken. The aneurysm was adhered to the IVC and the ileum and there was a large thrombotic mass in it. Aneurysmectomy and Y-graft interposition were done uneventfully. Pathology revealed marked thickness of the aorta and infiltration of lots of inflammatory cells. The culture of aneurysmal wall was negative. This is the very rare case because of sudden thrombotic occlusion of the mycotic abdominal aneurysm. Several important features of this disease have been also discussed.