Ciprofloxacin-Resistant Bacteria on Pre-Prostate Biopsy Rectal Swab Culture: A Northwest Ohio Study

Ciprofloxacin is given to patients routinely prior to trans-rectal prostate biopsy. However bacterial resistance to this antibiotic has increased nationally resulting in increased infectious complications after prostate biopsy. In our study we aimed to quantify the percentage of older northwestern Ohio males harboring ciprofloxacin-resistant bacteria in the rectal vault and to assess if resistance is increasing over time.

After Institutional Review Board approval, a retrospective chart review of all patients who underwent rectal swab culture within the Department of Urology at The University of Toledo Medical Center between January 1, 2012 and December 31, 2015 was completed. Patient demographic data were collected including the presence of ciprofloxacin resistance bacteria. To test for significant differences, χ² and analysis of variance (ANOVA) analyses were completed where applicable.

During the study period 311 swabs for resistant organisms were completed. The average age at time of swab was 64 (± 8.7 standard deviation [SD]) years old. Resistance rates were 13.2%, 13.8%, 19.5%, and 13.3% in 2012, 2013, 2014, and 2015, respectively. We found no statistically significant difference in resistances across years. Additionally, previous biopsy and age were not associated with ciprofloxacin resistance.

Resistance to ciprofloxacin in the rectal vaults of older northwestern Ohio males is significant but appears to be stable over the study period. Previous biopsy and increased age do not appear to be risk factors for fluoroquinolone resistance. Given the relatively high rate of resistance in our population we recommend rectal swabs prior to prostate biopsy to assist in antibiotic agent choice.