title: Predominance of a single restriction endonuclease analysis group with intrahospital subgroup diversity among Clostridium difficile isolates at two Chicago hospitals.
abstract: OBJECTIVE
  To determine the epidemiology and relatedness of Clostridium difficile isolates in two geographically separated hospitals in a large metropolitan area, each with unique patients and personneL DESIGN: Observational descriptive molecular epidemiology of clinical C. difficile isolates.
  
  
  METHODS
  Two tertiary-care hospitals in Chicago.
  
  
  METHODS
  Consecutive C. difficile isolates from the clinical laboratory of a Veterans Affairs hospital during a 13-month period were typed by restriction endonuclease analysis (REA). During an overlapping 3-month period, stool specimens that tested positive for C. difficile toxin from patients at a nearby county hospital were cultured and the recovered isolates typed by the same method.
  
  
  RESULTS
  Nineteen (68%) of 28 nosocomial isolates at the smaller, Veterans Affairs hospital belonged to REA group K. Within this group of closely related strains, 9 distinct REA types were recognized. Twenty-one (72%) of 29 nosocomial isolates at the larger, county hospital also belonged to group K. However, the predominant REA types within group K differed markedly at each institution.
  
  
  CONCLUSIONS
  These findings demonstrate a high degree of similarity among nosocomial C. difficile strains from different hospitals in the same city and suggest the possibility of an extended outbreak of a prototype group K strain with subsequent genetic drift at the two different institutions.
authors.affiliation: Department of Medicine, Chicago Healthcare System, Northwestern University Medical School, Illinois, USA.
authors.forename: Endale T
authors.initials: ET
authors.lastname: Mekonen
authors.forename: Dale N
authors.initials: DN
authors.lastname: Gerding
authors.forename: Susan P
authors.initials: SP
authors.lastname: Sambol
authors.forename: Jean M
authors.initials: JM
authors.lastname: Pottinger
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Pulvirenti
authors.forename: Dayle
authors.initials: D
authors.lastname: Marsh
authors.forename: Frank E
authors.initials: FE
authors.lastname: Kocka
authors.forename: Stuart
authors.initials: S
authors.lastname: Johnson
mesh_terms: D002641:Chicago / Q000453:epidemiology; D016360:Clostridioides difficile / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D003015:Clostridium Infections / Q000201:enzymology / Q000453:epidemiology* / Q000382:microbiology; D003428:Cross Infection / Q000201:enzymology / Q000453:epidemiology* / Q000382:microbiology; D004262:DNA Restriction Enzymes / Q000378:metabolism*; D004269:DNA, Bacterial / Q000235:genetics; D004196:Disease Outbreaks; D006766:Hospitals, County; D006787:Hospitals, Veterans; D006801:Humans; D017720:Molecular Epidemiology; D000091402:Prohibitins
chemical_list: D004269:DNA, Bacterial; C000717331:PHB2 protein, human; D000091402:Prohibitins; D004262:DNA Restriction Enzymes