title: Cross-transmission of clinical Enterococcus faecium in relation to esp and antibiotic resistance.
abstract: OBJECTIVE
  To investigate clonality among clinical Enterococcus faecium isolates and normal intestinal microflora isolates as well as cross-transmission between patients in relation to the presence of the esp gene and antibiotic resistance.
  
  
  RESULTS
  Blood-culture isolates (n = 101) deriving from tertiary, secondary and primary hospitals were analysed. Antibiotic susceptibility was investigated. Polymerase chain reaction and pulsed-field gel electrophoresis were used for detection of esp and genotyping, respectively. Nearly half (43%) of the patients included were involved in a cross-transmission event with Ent. faecium. These strains disseminated both within and between all hospitals. The antibiotic resistance and presence of esp were highest in isolates from the tertiary hospital. Isolates harbouring esp showed less genetic diversity compared with esp negative ones.
  
  
  CONCLUSIONS
  Cross-transmission with Ent. faecium between patients was readily detected, indicating that hospital-adapted clones circulate within and between hospitals. Acquired characteristics, such as antibiotic resistance and esp, seem to accumulate in the isolates disseminating in the tertiary hospital.
  
  
  CONCLUSIONS
  It is important to characterize Ent. faecium isolates causing infections and to determine the extent of dissemination in order to prevent further spread of these pathogens.
authors.affiliation: Division of Clinical Microbiology, Karolinska Institutet, Karolinska University Hospital, Huddinge, Stockholm, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Billström
authors.forename: A
authors.initials: A
authors.lastname: Sullivan
authors.forename: B
authors.initials: B
authors.lastname: Lund
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D016984:Enterococcus faecium / Q000145:classification* / Q000187:drug effects / Q000235:genetics; D006761:Hospitals; D006801:Humans; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction
chemical_list: D000900:Anti-Bacterial Agents