2062. Evaluation of Susceptibility Testing Methods for Fosfomycin Against Enterobacteriaceae and Pseudomonas aeruginosa

Is a New Standard Needed for Diffusion Methods for In Vitro Susceptibility Testing of Fosfomycin against Pseudomonas aeruginosa?

We analyzed fosfomycin susceptibility results in Pseudomonas aeruginosa clinical isolates obtained by MIC gradient strips and disk diffusion methods using two different inocula, 10(8) and 10(6) CFU/ml, and compared them to the agar dilution reference method. Essential and categorical agreements were 93.6% and 95%, respectively, for the 10(6) CFU/ml alternative inoculum, and they were 67.6% and ...

In vitro susceptibility testing of fosfomycin in Pseudomonas 1 aeruginosa , do we need a new standard for diffusion methods ?

In vitro activity of fosfomycin-gentamicin, fosfomycin-ceftazidime, fosfomycin-imipenem and ceftazidime-gentamicin combinations against ceftazidime-resistant Pseudomonas aeruginosa.

The effects of antimicrobial combinations against ceftazidime-resistant Pseudomonas aeruginosa strains isolated from hospitalized patients were investigated. Using the checkerboard titration method, combination of fosfomycin-gentamicin, fosfomycin-ceftazidime, fosfomycin-imipenem and ceftazidime-gentamicin was synergistic against 4, 11, 38 and 39% of 22, 18, 29 and 18 strains tested respectivel...

Comparison of four antimicrobial susceptibility testing methods to determine the in vitro activities of piperacillin and piperacillin-tazobactam against clinical isolates of Enterobacteriaceae and Pseudomonas aeruginosa.

Susceptibility to piperacillin was similar to that to piperacillin-tazobactam (<1% difference) for 6,938 isolates of Enterobacter aerogenes and 13,954 isolates of Enterobacter cloacae tested using a Vitek system; for the same species, in contrast, susceptibility rates to piperacillin-tazobactam were 5.9 to 13.9% higher than to piperacillin using disk diffusion, MicroScan, and Vitek 2 testing. U...

Fosfomycin Susceptibility in Urinary Tract Enterobacteriaceae.

Introduction Antibiotic treatment of Urinary Tract Infections (UTI) is becoming increasingly difficult due to emergence of multi-drug resistant (ESBLs, AmpC, CRE) uropathogens. Fosfomycin is an old antibiotic that has evoked renewed interest with unique properties of not sharing any structural similarity and lack of cross-resistance with other antimicrobial agents. Our aim is to evaluate in-vit...