title: MLST reveals potentially high-risk international clones of Enterobacter cloacae.
abstract: OBJECTIVE
  To perform the first multinational Enterobacter cloacae clonality study, using the MLST scheme newly developed in Japan.
  
  
  METHODS
  The analysis included 195 rectal carriage E. cloacae isolates resistant to expanded-spectrum cephalosporins (ESCs), collected from patients in 12 hospital units across Europe and Israel. All of the isolates were typed by PFGE and 173 isolates were subjected to MLST. ESC resistance was analysed phenotypically; genes encoding ESBLs and carbapenemases were identified by PCR and sequencing.
  
  
  RESULTS
  MLST distinguished 88 STs, which correlated with the PFGE data. PFGE was more discriminatory, producing 129 pulsotypes (169 patterns). Numerous STs were observed in several countries each. The most widespread were ST66, ST78, ST108 and ST114, each having at least 10 isolates from three to five countries, diversified into multiple pulsotypes, with clusters of related isolates in one or more centres. Analysis of the STs against the MLST database revealed several epidemic clonal complexes, such as those with central genotypes ST74 (including ST78) or ST114 (including ST66). ESC resistance was equally related to overexpression of the AmpC cephalosporinase and to ESBL production. Among ESBL producers some spreading subclones were identified, including specific ST66, ST78 and ST114 pulsotypes, associated with CTX-M-15 production. Several isolates produced carbapenemase VIM-1 or KPC-2.
  
  
  CONCLUSIONS
  Together with the information available in the MLST database, our results suggest that, like Escherichia coli and Klebsiella pneumoniae, E. cloacae harbours clonal lineages of increased epidemic potential that may be associated with resistance spread.
authors.affiliation: Department of Molecular Microbiology, National Medicines Institute, Warsaw, Poland radek@cls.edu.pl.
authors.forename: R
authors.initials: R
authors.lastname: Izdebski
authors.affiliation: Department of Molecular Microbiology, National Medicines Institute, Warsaw, Poland.
authors.forename: A
authors.initials: A
authors.lastname: Baraniak
authors.affiliation: Department of Molecular Microbiology, National Medicines Institute, Warsaw, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Herda
authors.affiliation: Department of Molecular Microbiology, National Medicines Institute, Warsaw, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Fiett
authors.affiliation: Department of Medical Microbiology and Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: M J M
authors.initials: MJ
authors.lastname: Bonten
authors.affiliation: Division of Epidemiology and Preventive Medicine, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel.
authors.forename: Y
authors.initials: Y
authors.lastname: Carmeli
authors.affiliation: Department of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium.
authors.forename: H
authors.initials: H
authors.lastname: Goossens
authors.affiliation: Department of Molecular Microbiology, National Medicines Institute, Warsaw, Poland.
authors.forename: W
authors.initials: W
authors.lastname: Hryniewicz
authors.affiliation: Service de reanimation médicale, INSERM, U957 & Université Paris-Est, Créteil, France.
authors.forename: C
authors.initials: C
authors.lastname: Brun-Buisson
authors.affiliation: Department of Molecular Microbiology, National Medicines Institute, Warsaw, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Gniadkowski
mesh_terms: D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology; D016972:Enterobacter cloacae / Q000145:classification* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*; D004756:Enterobacteriaceae Infections / Q000453:epidemiology* / Q000382:microbiology*; D005060:Europe / Q000453:epidemiology; D005838:Genotype; D006801:Humans; D007391:International Cooperation; D007557:Israel / Q000453:epidemiology; D058885:Multilocus Sequence Typing; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D001618:beta-Lactamases
keywords: E. cloacae; ESBLs; carbapenemases; population study