title: Antimicrobial susceptibilities of commonly encountered bacterial isolates to fosfomycin determined by agar dilution and disk diffusion methods.
abstract: We studied the antimicrobial activity of fosfomycin against 960 strains of commonly encountered bacteria associated with urinary tract infection using standard agar dilution and disk diffusion methods. Species studied included 3 common species of Enterobacteriaceae, Pseudomonas aeruginosa, Acinetobacter baumannii, and Stenotrophomonas maltophilia; methicillin-susceptible and -resistant Staphylococcus aureus; and vancomycin-susceptible and resistant Enterococcus faecalis and E. faecium. MICs and inhibition zone diameters were interpreted in accordance with both the currently recommended Clinical and Laboratory Standards Institute (CLSI) criteria for urinary tract isolates of Escherichia coli and Enterococcus faecalis and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria for Enterobacteriaceae. Tentative zone diameter interpretive criteria were developed for species not currently published by CLSI or EUCAST. Escherichia coli was uniformly susceptible to fosfomycin, as were most strains of Klebsiella pneumoniae and Enterobacter cloacae. A. baumannii was resistant to fosfomycin, while the prevalence of resistance in P. aeruginosa and S. maltophilia was greatly affected by the choice of MIC breakpoint. New tentative zone diameter criteria for K. pneumoniae, E. cloacae, S. aureus, and E. faecium were able to be set, providing some interim laboratory guidance for disk diffusion until further breakpoint evaluations are undertaken by CLSI and EUCAST.
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Hsin-Chu Branch, Hsin-Chu, Taiwan.
authors.forename: Ching-Lan
authors.initials: CL
authors.lastname: Lu
authors.forename: Chia-Ying
authors.initials: CY
authors.lastname: Liu
authors.forename: Yu-Tsung
authors.initials: YT
authors.lastname: Huang
authors.forename: Chun-Hsing
authors.initials: CH
authors.lastname: Liao
authors.forename: Lee-Jene
authors.initials: LJ
authors.lastname: Teng
authors.forename: John D
authors.initials: JD
authors.lastname: Turnidge
authors.forename: Po-Ren
authors.initials: PR
authors.lastname: Hsueh
mesh_terms: D040981:Acinetobacter baumannii / Q000187:drug effects; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004755:Enterobacteriaceae / Q000187:drug effects; D013293:Enterococcus faecalis / Q000187:drug effects; D005578:Fosfomycin / Q000494:pharmacology*; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D005578:Fosfomycin