title: Evaluation of Surrogate Disk Tests for Detection of Ciprofloxacin and Levofloxacin Resistance in Clinical Isolates of Salmonella enterica.
abstract: Detection of fluoroquinolone resistance in Salmonella enterica has become increasingly difficult due to evolving resistance mechanisms to this antimicrobial class in this organism. We evaluated two quinolone disks and five fluoroquinolone disks for their ability to act as a surrogate agent for the detection of fluoroquinolone resistance in a collection of 136 S. enterica isolates, including 111 with intermediate or resistant ciprofloxacin MICs mediated by a variety of resistance mechanisms. Ciprofloxacin, ofloxacin, and pefloxacin disks detected all isolates resistant to ciprofloxacin (0% very major error) and yielded false resistance (major error) in 8, 4, and 12% of susceptible isolates, respectively. Ciprofloxacin and pefloxacin provided clearer differentiation of susceptible and resistant isolates.
authors: Pathology and Laboratory Medicine, University of California, Los Angeles, California, USA Santa Clara Valley Medical Center, Santa Clara, California, USA.
authors: Eszter
authors: E
authors: Deak
authors: Statens Serum Institut, Copenhagen, Denmark.
authors: Robert
authors: R
authors: Skov
authors: Pathology and Laboratory Medicine, University of California, Los Angeles, California, USA.
authors: Janet A
authors: JA
authors: Hindler
authors: Pathology and Laboratory Medicine, University of California, Los Angeles, California, USA rhumphries@mednet.ucla.edu.
authors: Romney M
authors: RM
authors: Humphries
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002939:Ciprofloxacin / Q000494:pharmacology*; D027081:DNA Gyrase / Q000235:genetics; D052978:Disk Diffusion Antimicrobial Tests / Q000379:methods*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D006801:Humans; D064704:Levofloxacin / Q000494:pharmacology*; D019779:Salmonella enterica / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D002939:Ciprofloxacin; D064704:Levofloxacin; D027081:DNA Gyrase