title: Fecal colonization of Enterobacteriaceae carrying plasmid-mediated quinolone resistance determinants in Korea.
abstract: The aims of the current study were to investigate the prevalence and molecular characteristics of plasmid-mediated quinolone resistance (PMQR) genes from colonizing fecal organisms and to compare the incidence and subtype of these genes according to bacterial species and hospital at five tertiary-care hospitals in Korea. A total of 500 nonduplicated clinical isolates of Enterobacteriaceae were obtained from fecal specimens at five tertiary-care hospitals between March and May 2008. The PMQR genes (qnrA, qnrB, qnrS, aac(6')-Ib-cr, and qepA) were amplified by PCR and confirmed by direct sequencing of the PCR products. A total of 83 (16.6%) qnr-positive isolates were detected. The prevalence rates of qnrA, qnrB, and qnrS were 1.4%, 13.6%, and 1.6%, respectively. The species distributions of qnrB-positive isolates were Klebsiella pneumoniae (37/109; 33.9%), Citrobacter freundii (10/34; 29.4%), Citrobacter braakii (8/13; 61.5%), and Escherichia coli (8/275; 2.9%). Sixteen subtypes of qnrB were detected, including seven novel variants. The prevalences of aac(6')-Ib-cr and qepA were 15.6% (n=78) and 0.6% (n=3), respectively. The aac(6')-Ib-cr gene was detected in 39 (47.0%) of 83 qnr-positive isolates and 39 (9.4%) of 417 qnr-negative isolates There was one qepA variant containing a novel mutation (Ala231Val). The prevalence of PMQR genes was high in Enterobacteriaceae from stool specimens in Korea, and there was a close relation between qnr and aac(6')-Ib-cr.
authors.affiliation: Department of Laboratory Medicine, Inje University College of Medicine, 633-165 Gaegeum-dong Busanjin-gu, Busan, Korea.
authors.forename: Haeng Soon
authors.initials: HS
authors.lastname: Jeong
authors.forename: Il Kwon
authors.initials: IK
authors.lastname: Bae
authors.forename: Jeong Hwan
authors.initials: JH
authors.lastname: Shin
authors.forename: Si Hyun
authors.initials: SH
authors.lastname: Kim
authors.forename: Chulhun L
authors.initials: CL
authors.lastname: Chang
authors.forename: Joseph
authors.initials: J
authors.lastname: Jeong
authors.forename: Sunjoo
authors.initials: S
authors.lastname: Kim
authors.forename: Chae Hoon
authors.initials: CH
authors.lastname: Lee
authors.forename: Nam Hee
authors.initials: NH
authors.lastname: Ryoo
authors.forename: Jeong Nyeo
authors.initials: JN
authors.lastname: Lee
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics; D003227:Conjugation, Genetic; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D004755:Enterobacteriaceae / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D004756:Enterobacteriaceae Infections / Q000453:epidemiology* / Q000382:microbiology; D005243:Feces / Q000382:microbiology*; D006785:Hospitals, University; D006801:Humans; D008826:Microbial Sensitivity Tests; D010957:Plasmids / Q000235:genetics*; D016133:Polymerase Chain Reaction; D015363:Quinolones / Q000494:pharmacology*; D056910:Republic of Korea / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015363:Quinolones