Imipenem and ciprofloxacin consumption as factors associated with high incidence rates of resistant Pseudomonas aeruginosa in hospitals in northern France.

In France, Pseudomonas aeruginosa is the third most common isolate from nosocomial infections. To determine whether high consumption rates of some antibiotics are risk factors for resistance to ceftazidime, imipenem, ciprofloxacin and amikacin in P. aeruginosa, we conducted a study based on data from the Antimicrobial Surveillance Network in northern France and the French public reporting system of infection control indicators. These data were related to hospital characteristics (size, type, proportion of non-acute care beds), antibiotic consumption, incidence rates of some key resistances and quality indicators of healthcare-associated infection (HAI) control. In univariate analysis, high total and specific antibiotic consumption (except amoxicillin/clavulanate and imidazoles) were associated with high P. aeruginosa resistance rates. In multivariate analysis, high resistance rates were related to high imipenem and ciprofloxacin consumption [odds ratio (95% confidence interval): 7.9 (2.24-28.09), P<0.05 for both], but were not significantly related to quality indicators of HAI control. These findings suggest that imipenem and ciprofloxacin use could play a major role in driving P. aeruginosa resistance, independent of other infection control performance.