Psoas abscess in patients with an infected aortic aneurysm

Psoas abscess is an uncommon disease, and its presenting features are usually nonspecific. Infected aortic aneurysms could be complicated by psoas abscess.

A retrospective chart review was conducted to examine the incidence, clinical presentations, microbiology, and outcomes of psoas abscess in patients with an infected aortic aneurysm.

Between 1996 and 2007, 40 patients (32 men) with an infected infrarenal aortic aneurysm were treated in our hospital. Their median age was 71 years (range, 38 to 88 years). In 38 patients a blood or tissue culture had a positive result. The most common responsible pathogen was Salmonella spp in 29 patients (76%), followed by Staphylococcus aureus in 3 (8%), Escherichia coli in 2 (5%), Klebsiella pneumoniae in 3 (8%), and Mycobacterium tuberculosis in 1 (3%). One patient underwent endovascular repair but died. In-situ graft replacement was done in 32 patients. Persistent or recurrent infection occurred in seven (22%) of 32 operated on patients. The mortality rate was 86%, and the overall aneurysm-related mortality rate of in situ graft replacement was 22% (7/32). In eight (20%) of the 40 patients, aortic infection was complicated by psoas abscess. Infection complicated by psoas abscess was present in seven of 32 operated patients. It was associated with higher incidence of emergency operation, hospital mortality, prosthetic graft infection, and aneurysm-related mortality than infection without abscess.

Psoas abscess was common in patients with infected infrarenal aortic aneurysm. Salmonella spp was the most common pathogen. Psoas abscess was associated with a high mortality rate, emergency operation, and persistent infection.