title: Spontaneously occurring staphylococcal mutants resistant to clinically achievable concentrations of ciprofloxacin and temafloxacin.
abstract: The frequency of spontaneously occurring mutants resistant to 0.5, 1, 2, 4 and 8 micrograms of temafloxacin or ciprofloxacin per milliliter was documented with four Staphylococcus aureus and four Staphylococcus epidermidis strains. Resistant mutants were recovered at two- to four-fold the MIC of either drug, and they displayed cross-resistance to other fluoroquinolones. Resistance to temafloxacin occurred at frequencies lower than those observed with equal concentrations of ciprofloxacin. Resistance to greater than four-fold the MIC of either drug was not detected (frequencies less than 10(-10).
authors.affiliation: Clinical Microbiology Institute, Tualatin, Oregon 97062.
authors.forename: A L
authors.initials: AL
authors.lastname: Barry
authors.forename: M A
authors.initials: MA
authors.lastname: Pfaller
authors.forename: P C
authors.initials: PC
authors.lastname: Fuchs
mesh_terms: D000890:Anti-Infective Agents; D002939:Ciprofloxacin / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D024841:Fluoroquinolones; D008826:Microbial Sensitivity Tests; D009154:Mutation; D015363:Quinolones / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics; D013212:Staphylococcus epidermidis / Q000187:drug effects* / Q000235:genetics
chemical_list: D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D015363:Quinolones; C054745:temafloxacin; D002939:Ciprofloxacin