title: Characteristics of the Molecular Epidemiology of CTX-M-Producing Escherichia coli Isolated from a Tertiary Hospital in Daejeon, Korea.
abstract: The aims of this study were to characterize the molecular epidemiological profiles of CTX-M-producing uropathogenic Escherichia coli isolates from a tertiary hospital in Daejeon, Korea, and to investigate the genetic diversity and compare the prevalence of sequence types (STs) in different areas. Extended spectrum β-lactamase-producing E. coli strains isolated from urine were analyzed for CTX-M, integrons, and insertion sequence common regions (ISCRs) by PCR and sequencing. Multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), phylogenetic analysis, and rep-PCR were also used for molecular typing of the isolates. Of 80 CTX-M producers, 31 and 46 expressed CTX-M-15 and CTX-M-14, respectively. MLST analysis indicated that the most prevalent ST was ST131 (n = 34, 42.5%), followed by ST38 (n = 22, 27.5%), ST405 (n = 8, 10.0%), and ST69 (n = 6, 7.5%). Most CTX-M producers harbored class 1 integrons. ST131 strains belonged to phylogenetic group B2 and showed identical rep-PCR patterns, whereas ST69, ST38, and ST405 strains belonged to phylogenetic group D; the ST38 and ST405 strains displayed the same rep-PCR pattern, respectively. ST131 and ST38 isolates showed 21 and 19 distinct types, respectively, by PFGE. In Daejeon, D-ST38 CTX-M-14 producers were relatively more prevalent than in other countries and Korean cities. Our results indicate that CTX-M-producing E. coli isolates belonged mostly to ST131 or ST38 and were more related to hospital-onset than to community-onset infections and that the blaCTX-M gene may vary according to the ST.
authors.affiliation: Department of Laboratory Medicine, College of Medicine, Chungnam National University, Daejeon 34134, Republic of Korea.
authors.forename: Semi
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Biomedical Laboratory Science, Far East University, Eumseong 27601, Republic of Korea.
authors.forename: Ji Youn
authors.initials: JY
authors.lastname: Sung
authors.affiliation: Department of Biomedical Laboratory Science, Jeonju Kijeon College, Jeonju 54989, Republic of Korea.
authors.forename: Hye Hyun
authors.initials: HH
authors.lastname: Cho
authors.affiliation: Department of Laboratory Medicine, College of Medicine, Chungnam National University, Daejeon 34134, Republic of Korea.
authors.forename: Kye Chul
authors.initials: KC
authors.lastname: Kwon
authors.affiliation: Department of Laboratory Medicine, College of Medicine, Chungnam National University, Daejeon 34134, Republic of Korea.
authors.forename: Sun Hoe
authors.initials: SH
authors.lastname: Koo
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology; D006801:Humans; D017720:Molecular Epidemiology; D058885:Multilocus Sequence Typing; D056910:Republic of Korea / Q000453:epidemiology; D062606:Tertiary Care Centers; D014552:Urinary Tract Infections / Q000453:epidemiology / Q000382:microbiology; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D001618:beta-Lactamases
keywords: CTX-M-producing Escherichia coli; MLST; PFGE; molecular epidemiology