Arterial infections due to Listeria monocytogenes: report of four cases and review of world literature.

Early diagnosis and successful antimicrobial therapy have diminished the frequency of embolomycotic aneurysms, but infected aortic and small vessel aneurysms, arteriosclerotic plaques, and prosthetic grafts are becoming more common. A broad spectrum of pathogens, including Staphylococcus, Salmonella, Enterobacteriaceae, Pseudomonas aeruginosa, and some unusual organisms, are associated with this change. We treated four patients (three with abdominal aortic aneurysms and one with a prosthetic graft) with arterial infections caused by Listeria monocytogenes. Only seven other cases have previously been recorded in the world literature. Infection is suspected when a palpable or radiographically defined aneurysm is present with an otherwise obscure febrile illness. In about one-third of patients, blood cultures have yielded the pathogen. Newer imaging techniques have helped confirm the diagnosis. These infections are best managed by surgical resection in combination with long-term, appropriate antimicrobial therapy with ampicillin or sulfonamides. Unlike other adult listerial infection, except endocarditis, in arterial infection, immunosuppression and malignancy are not predisposing factors.