In vitro efficacy of antimicrobial-coated bladder catheters in inhibiting bacterial migration along catheter surface.

Most cases of catheter-related urinary tract infection are probably caused by organisms that migrate from the urethral meatus-catheter interface along the external surface of the catheter into the bladder. To examine the ability of bladder catheters coated with minocycline and rifampin to inhibit bacterial migration along the external surface of the catheter, a novel in vitro bladder model was used. Compared with uncoated catheters, antimicrobial-coated bladder catheters significantly impeded the migration of Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Enterococcus faecalis, and Candida albicans (bacteriuria developed at a mean of 2-5 days vs. 9-34 days, respectively, after bacterial contamination of the catheter). Although production of zones of inhibition by coated catheters may provide some protection against infection, there was no correlation between the size of zones of inhibition and level of efficacy in inhibiting bacterial migration in vitro. Examination of the clinical efficacy of these antimicrobial-coated bladder catheters is prudent.