Objective: Escherichia coli is the most common microorganism isolated from both community and hospital-acquired urinary tract infections. In our study, it was aimed to investigate the extended spectrum beta lactamase (ESBL) positivity and fosfomycin trometamol (FT) resistance rates in E. coli strains isolated from urine cultures sent to microbiology laboratory of our hospital.

Materials and Methods: The identification and antibiotic susceptibility testing of the bacteria considered to be uropathogenic in the urine cultures investigated in microbiology laboratory of our hospital between 2012 and 2013 were performed with VITEK 2 (BioMérieux, France) automated system. FT resistance and ESBL positivity were evaluated retrospectively in 1085 E. coli strains isolated.

Results: Three hundred and three of 1085 E. coli strains studied were determined to be ESBL positive (27.9%) and 782 ESBL negative. Fifteen (1.38 %) E. coli strains were resistant to FT, while 1070 E. coli strains were susceptible to FT is 1070. The difference between susceptibilities of ESBL positive and ESBL negative strains to fosfomycin was not found to be statistically significant (p>0.05).

Conclusion: In our study, FT resistance was found to be low which is compatible with other studies and also was found to have no relation with ESBL resistance. This can be explained with low level of resistance to FT, the chemical structure and different target regions of the drug compared with other antimicrobial agents and the absence of cross-resistance.