In vitro susceptibility of quinolone-resistant Escherichia coli isolates with and without producing extended-spectrum lactamase to fosfomycin trometamol

Abstract number: P1038

Ceran N., Adaleti R., Nakipoglu Y., Tasdemir S., Tasdemir C., Inan A., Aksaray S.

Objectives: The frequency of extended-spectrum-b-lactamase (ESBL)-producing E. coli strains has been increased in Turkey, and all of these isolates are recovered from outpatients with uncomplicated Urinary Tract Infections (UTIs). It is common to find that the same plasmid coding for ESBL is also contains genes conferring resistance to several groups of antimicrobial agents, such as aminoglycosides and cotrimoxazole. The concurrence of quinolone resistance, particularly in ESBL-producing strains, is frequent, there being few alternatives for the appropriate oral treatment of uncomplicated UTIs caused by ESBL-producing microorganisms. The aim of this study was to evaluate and compare the efficacy of Fosfomycin trometamol (FMT) in the treatment of quinolone resistant E. coli with and without ESBL.

Methods: One-hundred and twenty five of quinolones resistant E. coli strains isolated from urine of outpatients (68 strains) and hospitalised patients (57 strains) were screened for the presence of ESBL by double disk synergy test and the susceptibility of the strains to FMT was performed by disk diffusion methods. Clinical Laboratory Standard Institute (CLSI) criteria was considered in both methods.

Results: Twenty-eight (41.2%) of outpatients and 35 (61.4%) of hospitalised patients isolates, a total of 63 (50.4%) strains were revealed ESBL. All of the ESBL negative isolates were sensitive to FMT. Only two ESBL producing E. coli strains (3.2%) isolated from urine of hospitalised patients were found to be resistant to FMT.

Conclusion: The high efficacy of FMT against all tested ESBL positive and negative quinolone resistant E. coli, in addition to low side effects and pharmacokinetic properties, FMT could be a useful alternative for single-dose therapy of uncomplicated UTIs, especially in regions with high quinolone resistance E. coli infections.

Session Details

Date: 16/05/2009
Time: 00:00-00:00
Session name: 19th European Congress of Clinical Microbiology and Infectious Diseases
Location: Helsinki, Finland, 16 - 19 May 2009
Presentation type:
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