Ciprofloxacin-resistant Escherichia coli from bacteraemias in England; increasingly prevalent and mostly from men

Objectives: To assess ciprofloxacin resistance among Escherichia coli isolates from bacteraemia patients in England in relation to age, sex and Region. Methods: Routine susceptibility data for bacteraemia isolates were collected from over 90% of hospitals in England. Results: During 1995-2001, the prevalence of ciprofloxacin resistance trebled, from 2.1% to 6.5%. Isolates from men were more frequently resistant than those from women, possibly because infections in men more often involve nosocomial strains. Resistance was rare (<1.5%) in isolates from patients aged <1 year; among older patients, resistance was unrelated to age in isolates from women, but peaked in the 15-44 age group for men. Conclusions: The prevalence of ciprofloxacin resistance in E. coli from bacteraemia is strongly associated with sex and, to a lesser extent, age.