Antimicrobial lubricant reduces rectal bacteria at transrectal prostate biopsy:results from a prospective randomized trial

PURPOSE: Antibiotic resistance may lead to increasing infection rates at transrectal prostate biopsy. Local antimicrobial agents might help to reduce bacterial load. The aim of this study was to test the potency of antimicrobial lubricants to reduce local bacterial loads and specifically fluoroquinolone-resistant strains.

PATIENTS AND METHODS: Overall, 384 prostate biopsy (PBx) patients of a larger prospective randomized trial (n = 1000) were included. Patients were randomized for biopsy with pre-interventional instillation of an antimicrobial lubricant (intervention group n = 256) or with the standard lubricant (control group n = 128). Bacteria were recovered on pre- and post-biopsy rectal swab cultures from both patient groups. Bacterial colonization was semi-quantitatively recorded and analyzed for the presence of ciprofloxacin-resistant isolates.

RESULTS: Within the intervention group, where antimicrobial lubricant was instilled for PBx, the post-biopsy bacterial count was statistically significantly lower compared to prior biopsy bacterial count (p < 0.001), while in the control group, no statistically significant difference was shown. Moreover, our results demonstrated the tendency for reduction in ciprofloxacin-resistant bacteria growth when instillation of antimicrobial lubricant was used (9.4% versus 5.9%, p = 0.5 prior- and post-biopsy). No reduction in ciprofloxacin-resistant bacterial growth was demonstrated for the control group. Ciprofloxacin-resistance was shown in overall 30 (7.8%) patients.

CONCLUSION: Our data demonstrated that the antimicrobial lubricant prior biopsy leads to reduced bacterial load. Moreover, our data show the tendency for reduced ciprofloxacin-resistant bacteria growth when antimicrobial lubricant was instilled prior biopsy. However, the incidence of ciprofloxacin-resistant bacteria is low in our patient population. Rectal swabs should assess fluoroquinolone-resistance rates at prostate biopsy.