Antibiotic resistance in patients undergoing serial prostate biopsies: risk factors and impact on clinical outcomes

We evaluate the rate of developing ciprofloxacin resistance in patients undergoing repeat prostate biopsies (PBx), associated risk factors, and impact on complications.

We retrospectively evaluated pre-procedural rectal culture (RCx) data in men undergoing PBx from 1/1/2016 to 1/15/2021. Univariate and multivariate logistic regression were utilized to identify risk factors associated with development of antibiotic resistance. Complication rates were compared between ciprofloxacin-sensitive and ciprofloxacin-resistant patients.

A total of 743 men underwent initial RCx. Initial RCx detected ciprofloxacin resistance in 22% of patients. A history of diabetes (p = 0.01), > 2 prior prostate biopsies (p = 0.01), and ciprofloxacin use (p = 0.002) were significant risk factors for ciprofloxacin resistance on initial RCx. The rate of new ciprofloxacin resistance following biopsy with standard ciprofloxacin prophylaxis on 1st and 2nd exposure was 17.2% and 9.1% respectively. The number of biopsy cores, interval antibiotic exposure and interval procedures performed between first and second RCx were not significant predictors of developing ciprofloxacin resistance. Patients who received a non-ciprofloxacin antibiotic between first and second RCx did not develop ciprofloxacin resistance. Antibiotic resistance profile did not significantly affect the rate or type of complications after various prostate procedures.

Serial exposure to standard antibiotic prophylaxis for PBx and associated procedures can lead to development of ciprofloxacin resistance after each subsequent exposure. This carries important implications for serial biopsy and highlights the role for RCx prior to repeat biopsy.