ADSORPTION OF CIPROFLOXACIN TO URINARY CATHETERS AND EFFECT ON SUBSEQUENT BACTERIAL ADHESION AND SURVIVAL

The preincubation of urinary catheter material with minimum inhibitory and sub-inhibitory concentrations of ciprofloxacin caused a significant reduction in the adhesion of viable uropathogenic Escherichia coli subsequently exposed to the surfaces for periods of 1, 12, 24 and 48 h. In addition, the organisms which were adherent were seen by electron microscopy to be elongated and badly malformed. X-ray photoelectron spectroscopy indicated minor alteration in the C1s peak shape, a small decrease in the O/C and Si/C elemental surface concentration ratios and a slight increase in the N/C elemental surface concentration ratio upon preincubation of the catheters with ciprofloxacin, suggesting that a thin antibiotic film had adsorbed to the catheter after 1, 12 and 24 h incubation, Ultraviolet spectroscopy indicated that a concentration of 0.07 mug cm-3 ciprofloxacin had adsorbed within 1 h to the catheter. The exposure of young E. coli biofilms (formed over a 24 h period) to ciprofloxacin led to a significant killing effect within 24 h. These experiments demonstrated that ciprofloxacin could be a useful antibiotic for the prevention and early treatment of catheter-associated urinary tract infections.