Minimizing transrectal prostate biopsy-related infections; A prospective randomized trial of povidone-iodine intrarectal cleaning versus formalin needle disinfection

Abstract

Introduction: Transrectal prostate biopsies are associated with post biopsy infection and sepsis. We compared the efficacy of povidone-iodine rectal disinfection versus formalin needle disinfection in preventing post biopsy infection among patients undergoing transrectal ultrasound-guided prostate biopsy. Methods: Patients scheduled to undergo ultrasound-guided transrectal prostate biopsy (n = 621) over 20 months were randomized into 2 groups to receive either povidone-iodine intrarectal disinfection or formalin disinfection of needle after each core. These were compared to assess which methodology better prevented postprocedure infection. Statistical analysis were used to identify independent factors promoting infections. Results: Two hundred and ninety-eight patients from povidone-iodine intrarectal disinfection were compared with 300 from formalin needle disinfection group. Formalin needle disinfection was associated with significantly more infections (P = 0.02). Escherichia coli was the dominant pathogen, with >50% of cases being quinolone resistant. Type of disinfection (P = 0.002), BMI (P = 0.001), chronic prostatitis (P = 0.002), and diabetes mellitus (P = 0.01) were independent predictors of infections. BMI at 28.95 kg/m2 provided the best predictive cut-off point for infections, irrespective of method of disinfection. Area under the curve for all these parameters together was 0.91. Conclusions: We conclude that along with oral cephalosporin prophylaxis, povidone-iodine intrarectal disinfection is a superior to formalin needle disinfection alone in preventing post biopsy infection. Patients with BMI >28.95 kg/m2 should be considered at a higher risk for infections.