Efficacy of antimicrobial-impregnated bladder catheters in reducing catheter-associated bacteriuria: a prospective, randomized, multicenter clinical trial.

To examine the efficacy of bladder catheters impregnated with minocycline and rifampin in reducing catheter-associated bacteriuria. A prospective, randomized clinical trial was conducted at five academic medical centers. Patients undergoing radical prostatectomy were randomized to receive intraoperatively either regular silicone bladder catheters (control catheters) or silicone bladder catheters impregnated with minocycline and rifampin (antimicrobial-impregnated catheters). Catheters remained in place for a mean of 2 weeks. Urine cultures were obtained at about 3, 7, and 14 days after catheter insertion. Bacteriuria was defined as the growth of organism(s) in urine at a concentration of 10(4) colony-forming units per milliliter or greater. Kaplan-Meier analysis demonstrated that it took significantly longer for patients (n = 56) who received the antimicrobial-impregnated catheters to develop bacteriuria than those (n = 68) who received the control catheters (P = 0.006 by the log-rank test). Patients who received the antimicrobial-impregnated catheters had significantly lower rates of bacteriuria than those in the control group both at day 7 (15.2% versus 39.7%) and at day 14 (58.5% versus 83.5%) after catheter insertion. Patients who received the antimicrobial-impregnated catheters had significantly lower rates of gram-positive bacteriuria than the control group (7.1% versus 38.2%; P <0.001) but similar rates of gram-negative bacteriuria (46.4% versus 47.1%) and candiduria (3.6% versus 2.9%). The antimicrobial-impregnated catheters provided zones of inhibition against Enterococcus faecalis and Escherichia coli, both at baseline and on removal. Bladder catheters impregnated with minocycline and rifampin significantly reduced the rate of gram-positive catheter-associated bacteriuria up to 2 weeks after catheter insertion.