Escherichia coli: Epidemiology and analysis of risk factors for infectionscaused by resistant strains

This study analyzes the epidemiology of hospital and community-acquired inf ections caused by Escherichia coli. The antimicrobial resistance pattern wa s used to characterize the isolates, and a prospective observational study was performed to assess the relationship between antimicrobial use and bact erial resistance. The study was conducted during a 3-month period in a 1,20 0-bed tertiary care hospital in Nantes, France. An E. coli infection was di agnosed in 3.8% of the patients (507 of 13,384) admitted to the hospital be tween 1 January and 31 March 1996. Of the 507 isolates, 205 (40.4%) were re sistant to at least one antimicrobial; 40% were resistant to amoxicillin, 3 0% to amoxicillin/clavulanate, 38% to ticarcillin, and 16% to trimethoprim- sulfamethoxazole, while resistance to other antimicrobials was low. Prior r eceipt of antimicrobial and/or immunosuppressive therapy was significantly associated with infection caused by a resistant organism.