Short communication: comparison of susceptibilities of Escherichia coli urinary tract isolates against fosfomycin tromethamine and different antibiotics

The aim of this study was to investigate the susceptibilities of Escherichia coli strains isolated from urine samples, against fosfomycin tromethamine and different antibiotics in the period of October-December 2004 in a local hospital in Ankara, Turkey. A total of 120 E. coli strains isolated from urine cultures of subjects who were admitted to outpatient clinics were included to the study. The identification and antimicrobial susceptibility tests (against amikacin, amoxicillin/clavulanate, ampicillin, cefepime, cefoxitin, cefotaxime, cefuroxime, cefalotin, ciprofloxacin, gentamicin, levofloxacin, meropenem, nitrofurantoin, piperacillin, piperacillin/tazobactam and trimethoprim/sulphametoxazole) were performed by a commercial automatized system (Phoenix, Becton Dickinson, USA). Fosfomycin tromethamine susceptibility was studied by Kirby Bauer disk diffusion method according to the CLSI criteria. Only one strain (0.8%) was found resistant to fosfomycin tromethamine, while no resistance was determined against amikacin and meropenem. Most of the isolates were found susceptible to nitrofurantoin (90%), cefoxitin (82.5%), gentamicin (81%), piperacillin/tazobactam (81%), cefepime (79%) and cefotaxime (%79%). All of the E. coli isolates which were resistant to ciprofloxacin and levofloxacin (44% and 43%, respectively) were found susceptible to fosfomycin tromethamine. In conclusion, since E. coli is by far the most prevalent community acquired urinary tract pathogen, fosfomycin tromethamine seems to be a reasonable alternative for the ampirical therapy of uncomplicated urinary tract infections.