title: Investigation of plasmid-mediated quinolone resistance among isolates obtained in a Turkish intensive care unit.
abstract: The aim of this study was to search for three plasmid-encoded, quinolone-resistant determinants: qnrA, qnrB, and qnrS. Thus, 460 Gram-negative strains belonging to 11 different genera (clinical, 347; non-clinical, i.e., from a rectal swab, 113), of which 40% were ciprofloxacin-resistant, were recovered from patients in an intensive care unit at the Istanbul Medical Faculty, Turkey, in the years 2000 and 2006. PCR with primers specific for qnrA, qnrB, and qnrS genes and primers specific for a series of ESBL genes were used. One qnrB1 and two qnrS1 genes were identified in three ESBL-positive isolates, whereas no qnrA-positive strain was found. The qnrB1 determinant was identified in a ciprofloxacin-susceptible Enterobacter cloacae isolate that expressed CTX-M-15 beta-lactamase. Two qnrS1-determinants were found in two ciprofloxacin-susceptible E. cloacae isolates that were clonally related, but that had been isolated from different patients; both of these isolates expressed the same ESBL, CTX-M-3. This study detected the first plasmid-mediated quinolone-resistance determinants qnrB1 and qnrS1, among clinical strains obtained from patients in Turkey.
authors.affiliation: Department of Microbiology and Clinical Microbiology, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey. hasannazik01@gmail.com
authors.forename: Hasan
authors.initials: H
authors.lastname: Nazik
authors.forename: Betigül
authors.initials: B
authors.lastname: Ongen
authors.forename: Nuray
authors.initials: N
authors.lastname: Kuvat
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics; D002939:Ciprofloxacin / Q000494:pharmacology; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology / Q000382:microbiology; D006801:Humans; D007362:Intensive Care Units; D008826:Microbial Sensitivity Tests; D010957:Plasmids / Q000235:genetics*; D015995:Prevalence; D015363:Quinolones / Q000494:pharmacology*; D014421:Turkey / Q000453:epidemiology
chemical_list: D000890:Anti-Infective Agents; D001426:Bacterial Proteins; D015363:Quinolones; D002939:Ciprofloxacin