title: The dissemination mode of drug-resistant genes in Enterobacter cloacae.
abstract: BACKGROUND
  Enterobacter cloacae (E. cloacae) infection has the highest mortality rate among Enterobacter infections. This study aimed to determine the prevalence and the transmission route of the class I integron, qnr genes, and CTX-M ESBLs genes in clinical isolates and to analyse the association between the prevalence of MDR genes and the antibiotic resistance of E. cloacae.
  
  
  METHODS
  The antibiotic susceptibility was tested the agar dilution method. The class I integron, qnr genes, and CTX-M ESBLs genes were detected by polymerase chain reaction (PCR). The prevalence data were analysed with the Chi-square test.
  
  
  RESULTS
  In the 100 clinical isolates, the class I integron-positive rate was 65%, with 12% on chromosome, 15% on plasmids and 38% on both. The positive rate of qnr genes was 37% with plasmid location. The positive rates for qnrA, qnrB and qnrS were 6%, 23% and 8%, respectively. The CTX-M ESBLs-positive rate was 34%. For CTX-M-1 ESBLs, 15% were on chromosome, 6% on plasmids and 4% on both; for CTX-M-9 ESBLs, 1% was on chromosome and 7% on plasmid; for CTX-M-25 ESBLs, 3% were on chromosome and 1% on plasmid.
  
  
  CONCLUSIONS
  Antibiotic resistance genes may be horizontally and vertically disseminated among E. cloacae, which helps multidrug-resistant (MDR) strains of E. cloacae to be successful nosocomial agents.
authors: J
authors: J
authors: Liu
authors: T
authors: T
authors: Zeng
authors: G
authors: G
authors: Su
authors: L Y
authors: LY
authors: Lin
authors: Y
authors: Y
authors: Zhao
authors: W Q
authors: WQ
authors: Yang
authors: W X
authors: WX
authors: Xie
authors: Department of Microbiology and Immunology, Guangdong Medical College, Zhanjiang, China.
authors: Z G
authors: ZG
authors: Zhao
authors: G M
authors: GM
authors: Li
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D016972:Enterobacter cloacae / Q000187:drug effects* / Q000235:genetics*; D004756:Enterobacteriaceae Infections / Q000382:microbiology*; D005798:Genes, Bacterial; D006801:Humans; D032023:Integrons; D001618:beta-Lactamases / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases