Significance of Targeted Antimicrobial Prophylaxis Using Rectal-culture Selective Screening Media Prior to Transrectal Prostate Biopsy: A Multicenter, Randomized Controlled Trial

Objective: To examine whether antimicrobial prophylaxis based on screening rectal cultures using selective media prevented acute bacterial prostatitis following transrectal prostate biopsy (TRPB).

Methods: In this multicenter, randomized controlled trial, we enrolled 403 patients undergoing TRPB with low risks of infectious complications. Patients were randomized into a cultured group (CG) or no cultured group (NCG). In the CG, patients with positive-culture results for fluoroquinolone (FQ)-resistant or extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (E. coli) used piperacillin/tazobactam as prophylaxis, and those with negative-culture results and in the NCG used levofloxacin. The primary endpoint was the incidence of acute prostatitis after TRPB. The secondary endpoint was the accuracy of the selective media.

Results: Of 373 patients (CG, 187; NCG, 186), 67 were positive, and 120 were negative for rectal culture in the CG. The overall incidence of prostatitis after TRPB was 1.1% (n=4). The incidences in the CG and the NCG were 1.6% (n=3, all negative-culture cases) and 0.5% (n=1), respectively, without significant difference (P=.3). No prostatitis occurred in the positive-culture group. The sensitivity and specificity of the levofloxacin-insusceptible selective media were 98.1% and 94.7%, respectively.

Conclusion: Screening with selective media before TRPB in patients with low infectious risks may provide additive value to preventing post-biopsy prostatitis. Piperacillin/tazobactam can be considered when FQ-resistant or ESBL-producing E. coli is detected.