Fosfomycin in vitro resistance of Escherichia coli from the community

Abstract

We declare no confl ict of interest. Fosfomycin in vitro resistance of Escherichia coli from the communityIt is common practice in many places all over Brazil to use fosfomycin in the treatment of uncomplicated urinary tract infections, although resistance profi le is not currently well-known in our country.We would like to report the fi ndings of in vitro activity of fosfomycin against 240 nonduplicate consecutive E. coli strains isolated from community urinary samples (> 10 5 CFU/ mL in October 2009) from Curitiba (Paraná, Brazil). Susceptibility test were performed according to CLSI, using disk diffusion with 200 mg of fosfomycin disk with zone diameter breakpoint as recommended by CLSI.1 Clinical data were not evaluated and no statistical analysis was performed, considering the descriptive nature of the study.The susceptibility of E. coli to fosfomycin was 98.8% and to other antibiotics ranged from 66.3 -99.2% as follows: sulfamethoxazole (66.3%), nalidixic acid (78.3%), quinolones (81.3%, including ciprofl oxacin, levofl oxacin and norfl oxacin), amoxicillin/clavulanic acid (88.7%), nitrofurantoin (99.2%) and ceftriaxone (99.2%).In the present study E. coli isolates from patients with urinary infection were highly susceptible to fosfomycin. These data suggest that fosfomycin may be a good alternative for fi rst line antimicrobial treatment of uncomplicated low urinary tract infections.

In vitro susceptibility to fosfomycin in clinical and environmental extended-spectrum beta-lactamase producing and/or ciprofloxacin-non-susceptible Escherichia coli isolates

“…Resistance to fosfomycin was observed in 16 (5%) and 21 (6.6%) clinical urine samples according to the CLSI and EUCAST breakpoints, respectively. These isolates were geographically scattered in nine of 10 sanitary districts, and the resistance profile was higher than that previously reported in the same city 24 . Interestingly, fosfomycin resistance was higher in the ESBL-producing isolates in our study than in a previous study by Tuon et al 25 in carbapenemase-producing Klebsiella pneumoniae 10 years ago.…”

Evaluation of the in vitro activity of fosfomycin tromethamine against Gram-negative bacterial strains recovered from community- and hospital-acquired urinary tract infections in Turkey

“…Co-trimoxazole is the recommended drug for the treatment of UTIs in settings where the resistance is <10-20%, 18 and quinolones are the drugs of choice if the co-trimoxazole resistance is higher than 20%. 25 Several studies have shown ciprofloxacin and cotrimoxazole to be highly active against E. coli, with susceptibility rates over 81-99% 17,18,20,21,26,27 and 64-82%, 17,18,21,26,27 respectively, in contrast to dramatically decreasing susceptibility rates among ESBL-producers for ciprofloxacin and co-trimoxazole, 19-36% and 33-43%, respectively. 2,5 In this study, lower susceptibility rates for ciprofloxacin and co-trimoxazole were obtained: 70.5% and 38.3% in E. coli, and 81.3% and 69.2% in Klebsiella spp, respectively.…”

Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae: In vitro Susceptibility to Fosfomycin, Nitrofurantoin and Tigecycline

“…In a survey of 428 ESBL-producing isolates in Spain, fosfomycin resistance was 0.3 and 7.2% in E. coli and K. pneumoniae, respectively [9]. In Brazil, where there is high usage of fosfomycin, up to 98.8% of E. coli isolates from community-acquired UTIs were fosfomycin sensitive [10]. Our findings of 100% susceptibility among the ESBL-producing isolates tested provide further supportive evidence for recommending fosfomycin for the management of community acquired ESBL-producing urinary isolates.…”