title: The Widespread Presence of a Multidrug-Resistant Escherichia coli ST131 Clade among Community-Associated and Hospitalized Patients.
abstract: OBJECTIVE
  The extent of entry of multidrug-resistant Escherichia coli from the community into the hospital and subsequent clonal spread amongst patients is unclear. To investigate the extent and direction of clonal spread of these bacteria within a large teaching hospital, we prospectively genotyped multidrug-resistant E. coli obtained from community- and hospital associated patient groups and compared the distribution of diverse genetic markers.
  
  
  METHODS
  A total of 222 E. coli, classified as multi-drug resistant according to national guidelines, were retrieved from both screening (n = 184) and non-screening clinical cultures (n = 38) from outpatients and patients hospitalized for various periods. All isolates were routinely genotyped using an amplified fragment length polymorphism (AFLP) assay and real-time PCR for CTX-M genes. Multi-locus sequence typing was additionally performed to confirm clusters. Based on demographics, patients were categorized into two groups: patients that were not hospitalized or less than 72 hours at time of strain isolation (group I) and patients that were hospitalized for at least 72 hours (group II).
  
  
  RESULTS
  Genotyping showed that most multi-drug resistant E. coli either had unique AFLP profiles or grouped in small clusters of maximally 8 isolates. We identified one large ST131 clade comprising 31% of all isolates, containing several AFLP clusters with similar profiles. Although different AFLP clusters were found in the two patient groups, overall genetic heterogeneity was similar (35% vs 28% of isolates containing unique AFLP profiles, respectively). In addition, similar distributions of CTX-M groups, including CTX-M 15 (40% and 44% of isolates in group I and II, respectively) and ST131 (32% and 30% of isolates, respectively) were found.
  
  
  CONCLUSIONS
  We conclude that multi-drug resistant E. coli from the CTX-M 15 associated lineage ST131 are widespread amongst both community- and hospital associated patient groups, with similar genetic diversity and similar distributions of genetic markers.
authors.affiliation: Department of Medical Microbiology, Maasstad Hospital, Rotterdam, The Netherlands.|Department of Medical Microbiology and Infectious Diseases, Erasmus Medical Centre Rotterdam, The Netherlands.
authors.forename: P Martijn
authors.initials: PM
authors.lastname: den Reijer
authors.affiliation: Department of Medical Microbiology, Maasstad Hospital, Rotterdam, The Netherlands.
authors.forename: Sebastian
authors.initials: S
authors.lastname: van Burgh
authors.affiliation: Department of Medical Microbiology, Maasstad Hospital, Rotterdam, The Netherlands.
authors.forename: Arjan
authors.initials: A
authors.lastname: Burggraaf
authors.affiliation: Department of Medical Microbiology, Maasstad Hospital, Rotterdam, The Netherlands.|Department of Medical Microbiology and Infectious Diseases, Erasmus Medical Centre Rotterdam, The Netherlands.
authors.forename: Jacobus M
authors.initials: JM
authors.lastname: Ossewaarde
authors.affiliation: Department of Medical Microbiology, Maasstad Hospital, Rotterdam, The Netherlands.
authors.forename: Anneke
authors.initials: A
authors.lastname: van der Zee
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology; D003428:Cross Infection / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics; D004927:Escherichia coli Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000235:genetics; D005260:Female; D005819:Genetic Markers / Q000235:genetics; D060005:Genotyping Techniques; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058885:Multilocus Sequence Typing; D009426:Netherlands / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents; D005819:Genetic Markers