[In vitro activity of fosfomycin against ESBL-producing enterobacteria of urinary origin].

In vitro activity of fosfomycin, compared with other antibiotics used for urinary tract infections (UTI), against extended spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae clinical isolates obtained from UTIs, was determined. The activity of fosfomycin, co-trimoxazole, ciprofloxacin, nitrofurantoin, amoxicillin/clavulanic acid and gentamicin against 71 ESBL-producing E. coli clinical isolates and 13 ESBL-producing K. pneumoniae clinical isolates obtained from UTI was studied by the agar-dilution method or E-test. E. coli isolates produced mainly CTX-M type ESBL (76.1%), especially CTX-M 14 (56.3%). K. pneumoniae isolates produced most predominantly SHV-type ESBL (92.3%), mainly SHV-2 (76.9%). Gentamicin (4.4%), fosfomycin (5.6%) and nitrofurantoin (5.6%) showed the lowest resistance proportions against E. coli. Co-trimoxazole and ciprofloxacin (7.7%) showed the lowest resistance proportions against K. pneumoniae.