title: An outbreak of multi-drug resistant Escherichia coli urinary tract infection in an elderly population: a case-control study of risk factors.
abstract: BACKGROUND
  Prevention of infection due to multi-drug resistant organisms is particularly challenging because of the spread of resistant bacteria beyond hospitals into the community, including nursing homes. This study aimed to identify risk factors for the acquisition of a multidrug resistant (MDR) Escherichia coli in a local outbreak.
  
  
  METHODS
  Study participants were all aged over 65 years. Cases had the MDR E. coli isolated from a routine urine sample, and controls had a urine sample submitted to the laboratory in the same time period but the MDR E. coli was not isolated. Information from clinical records was used to identify risk factors both in the hospital and the community setting for acquisition of the MDR E. coli.
  
  
  RESULTS
  76 cases and 156 controls were identified and included in the study. In a multivariate analysis, risk factors statistically significantly associated with acquisition of the MDR E. coli were female gender (adjusted OR 3.2; 95 % confidence interval 1.5-6.9), level of care (high dependency OR 7.5; 2.2-25.7) compared with living independently), and in hospital prescription of antimicrobials to which the MDR E. coli was resistant (OR 5.6; 2.5-12.9).
  
  
  CONCLUSIONS
  The major risk factors for the acquisition of a MDR E. coli were found to be residence in a nursing home and in-hospital prescription of antimicrobials to which the MDR E. coli was resistant. This emphasises that prevention of transmission of MDROs within a community needs to involve both hospitals and also other healthcare organizations, in this case nursing homes.
authors.affiliation: Microbiology, Christchurch School of Medicine University of Otago, Christchurch, New Zealand. rbi@cyberxpress.co.nz.
authors.forename: Rosemary
authors.initials: R
authors.lastname: Ikram
authors.affiliation: Department of Preventive and Social Medicine, University of Otago, Dunedin, New Zealand. rpsutka@ucalgary.ca.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Psutka
authors.affiliation: Microbiology, Christchurch School of Medicine University of Otago, Christchurch, New Zealand. lac@paradise.net.nz.
authors.forename: Alison
authors.initials: A
authors.lastname: Carter
authors.affiliation: Department of Preventive and Social Medicine, University of Otago, Dunedin, New Zealand. patricia.priest@otago.ac.nz.
authors.forename: Patricia
authors.initials: P
authors.lastname: Priest
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016022:Case-Control Studies; D004269:DNA, Bacterial / Q000032:analysis / Q000302:isolation & purification; D003924:Diabetes Mellitus, Type 2 / Q000150:complications; D004196:Disease Outbreaks; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000235:genetics / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D009735:Nursing Homes; D016017:Odds Ratio; D012008:Recurrence; D012307:Risk Factors; D012737:Sex Factors; D014552:Urinary Tract Infections / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial