Empiric treatment of uncomplicated urinary tract infection with fluoroquinolones in older women in Israel: another lost treatment option?

BACKGROUND: Current guidelines for the treatment of uncomplicated urinary tract infection (UTI) in women recommend empiric therapy with antibiotics for which local resistance rates do not exceed 10-20%. We hypothesized that resistance rates of Escherichia coli to fluoroquinolones may have surpassed this level in older women in the Israeli community setting. OBJECTIVES: To identify age groups of women in which fluoroquinolones may no longer be appropriate for empiric treatment of UTI. METHODS: Resistance rates for ofloxacin were calculated for all cases of uncomplicated UTI diagnosed during the first 5 months of 2005 in a managed care organization (MCO) in Israel, in community-dwelling women aged 41-75 years. The women were without risk factors for fluoroquinolone resistance. Uncomplicated UTI was diagnosed with a urine culture positive for E. coli. The data set was stratified for age, using 5 year intervals, and stratum-specific resistance rates (% and 95% CI) were calculated. These data were analyzed to identify age groups in which resistance rates have surpassed 10%. RESULTS: The data from 1291 urine cultures were included. The crude resistance rate to ofloxacin was 8.7% (95% CI 7.4 to 10.2). Resistance was lowest among the youngest (aged 41-50 y) women (3.2%; 95% CI 1.11 to 5.18), approached 10% in women aged 51-55 years (7.1%; 95% CI 3.4 to 10.9), and reached 19.86% (95% CI 13.2 to 26.5) among the oldest women (aged 56-75 y). CONCLUSIONS: Physicians who opt to treat UTI in postmenopausal women empirically should consider prescribing drugs other than fluoroquinolones. Concomitant longitudinal surveillance of both antibiotic utilization patterns and uropathogen resistance rates should become routine practice in this managed-care organization.