Artificial urinary sphincter infection: causative organisms in a contemporary series

Traditionally Staphylococcus epidermidis has been the primary organism responsible for genitourinary prosthetic infection. However, the increasing prevalence of S. aureus infection poses a serious problem. We determined the organisms that produce artificial urinary sphincter infection in a contemporary series.

A single-institution, retrospective study was performed examining men undergoing artificial urinary sphincter explantation surgery between January 1997 and January 2007. Patients with clinical signs of infection at surgery were selected for study.

Infection was noted in 23 patients, including 5 implanted at other institutions. The median age was 72 years (IQR 70-76). The median interval from artificial urinary sphincter implantation or revision to explantation was 110 days (IQR 38-199). Culture of the periprosthetic fluid at the time of explantation was positive in 20 of 23 patients. Gram-positive cocci were cultured from 13 patients, including S. aureus in 7, S. epidermidis in 5 and Enterococcus in 1. Methicillin resistant S. aureus and S. epidermidis in 3 cases each represented a considerable proportion of isolated organisms (6 of 26 or 26%). Gram-negative bacilli were cultured from 6 patients and yeast was cultured from 1.

In this contemporary series S. aureus was the most common organism producing artificial urinary sphincter infection. Methicillin resistant S. aureus and S. epidermidis are often cultured during artificial urinary sphincter explantation due to infection. Strategies to prevent artificial urinary sphincter infection should target methicillin resistant S. aureus and S. epidermidis as well as gram-negative pathogens.