title: Susceptibility of Staphylococcus species and subspecies to fleroxacin.
abstract: Twenty-four Staphylococcus species or subspecies were examined for their susceptibilities to the fluoroquinolone fleroxacin (Ro 23-6240) by disk diffusion (5-micrograms disk) and by agar dilution for the determination of MICs. Resistant strains were further tested for their susceptibilities to oxacillin and the fluoroquinolone ciprofloxacin. Reference strains of the novobiocin-resistant species (Staphylococcus saprophyticus, Staphylococcus cohnii, Staphylococcus xylosus, Staphylococcus arlettae, and Staphylococcus gallinarum) had an intrinsic intermediate susceptibility (MIC, 4 micrograms/ml) to fleroxacin. Fleroxacin resistance was not observed in the reference strains of the novobiocin-susceptible species (MIC, 0.5 to 2.0 micrograms/ml). Clinical isolates of coagulase-negative species were generally less susceptible to fleroxacin than were reference strains. Seven percent of the Staphylococcus epidermidis clinical strains were resistant (MIC, greater than or equal to 8 micrograms/ml) to fleroxacin. Of these strains, 77% were resistant to oxacillin and 50% were resistant to ciprofloxacin. Thirty-four percent of the Staphylococcus haemolyticus clinical strains were resistant to fleroxacin, and 9% had intermediate susceptibility. Of the resistant strains, 95% were resistant to oxacillin and 77% were resistant to ciprofloxacin, while 23% had intermediate susceptibility to ciprofloxacin. Fleroxacin is an effective antimicrobial agent against most staphylococci.
authors.affiliation: Department of Microbiology, North Carolina State University, Raleigh 27695-7614.
authors.forename: T L
authors.initials: TL
authors.lastname: Bannerman
authors.forename: D L
authors.initials: DL
authors.lastname: Wadiak
authors.forename: W E
authors.initials: WE
authors.lastname: Kloos
mesh_terms: D000818:Animals; D016576:Fleroxacin / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D012867:Skin / Q000382:microbiology; D013210:Staphylococcus / Q000187:drug effects*
chemical_list: D016576:Fleroxacin