The impact of an antibiotic coating on the artificial urinary sphincter infection rate

In April 2008 InhibiZone® antibiotic coated artificial urinary sphincters were introduced. The antibiotic coating significantly increased the cost of the device by an average of $1,300 per artificial urinary sphincter. To our knowledge, no clinical data to date support the theory that this antibiotic coating decreases the risk of artificial urinary sphincter infection. Therefore, we compared infection rates in our cases before and after the introduction of InhibiZone coated artificial urinary sphincters to determine whether the coating decreased the device infection rate.

We retrospectively reviewed the records of 426 consecutive patients in whom an artificial urinary sphincter was implanted by a single surgeon from January 2005 to June 2012. Patients were divided equally into 213 consecutive males who received an artificial urinary sphincter without the antibiotic coating from January 2005 to March 2008 and 213 consecutive males implanted with the antibiotic coated artificial urinary sphincter from April 2008 to June 2012. Demographics and infection rates were compared.

Patient mean age, associated comorbidities and complexity were almost identical in the groups with and without the antibiotic coating, and infection rates were identical at 7 patients (3.3%) per group (p = 0.99). In the more complex patient subgroup with revision the antibiotic coating did not impact the infection rate. Infection developed in 2 of 50 patients (5%) with the antibiotic coated device and in 3 of 38 (6%) with the uncoated device (p = 0.42).

The InhibiZone coating of the artificial urinary sphincters did not alter the infection rate in our study. The added cost of the antibiotic coated artificial urinary sphincters (total of approximately $276,000 more for all 213 coated devices) was of no benefit in our series. Based on this assessment, we will transition to using artificial urinary sphincters without InhibiZone in our practice.