title: Descriptive epidemiology and case-control study of patients colonized with vancomycin-resistant enterococcus and methicillin-resistant Staphylococcus aureus.
abstract: BACKGROUND
  Patients colonized or infected with vancomycin-resistant enterococcus and methicillin-resistant Staphylococcus aureus may be at risk of acquiring vancomycin-resistant S. aureus if the vanA gene is transferred from vancomycin-resistant enterococcus to methicillin-resistant S. aureus.
  
  
  OBJECTIVE
  Our goal was to identify risk factors for cocolonization or coinfection (CC/CI) with vancomycin-resistant enterococcus and methicillin-resistant S. aureus.
  
  
  METHODS
  We conducted a descriptive, epidemiologic study of all patients with CC/CI identified from January 1998 to May 2003 and a nested case-control study of a cohort of patients hospitalized in the burn and wound unit.
  
  
  METHODS
  We conducted our study in a 813-bed tertiary care university teaching hospital.
  
  
  METHODS
  The study population consisted of patients found to have CC/CI during the study period.
  
  
  METHODS
  Descriptive epidemiologic data were collected from hospital records of all patients identified as having CC/CI. A subset of patients hospitalized in the burn and wound unit were included in a case-control study.
  
  
  RESULTS
  CC/CI was detected in 71% of the patients during a single hospital stay. The burn and wound unit, which does active surveillance for both organisms, and the general medicine unit, which does not do active surveillance for either organism, cared for more than one-half of these patients. Among patients being cared for in the burn and wound unit, having exposure to 2 or more invasive devices (central venous catheters, indwelling urinary catheters, and enteral feeding tubes) and renal insufficiency were independent risk factors for CC/CI.
  
  
  CONCLUSIONS
  Patients with CC/CI are the population at greatest risk for vancomycin-resistant S. aureus colonization or infection. The number of invasive devices to which patients are exposed and, thus, possibly the patients' underlying severity of illness, as well as renal insufficiency, appear to be risk factors for CC/CI.
authors.affiliation: Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA.
authors.forename: Bryndis
authors.initials: B
authors.lastname: Sigurdardottir
authors.forename: Jeffery Vande
authors.initials: JV
authors.lastname: Berg
authors.forename: Jianfang
authors.initials: J
authors.lastname: Hu
authors.forename: Josiah
authors.initials: J
authors.lastname: Alamu
authors.forename: Louise-Anne
authors.initials: LA
authors.lastname: McNutt
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Diekema
authors.forename: Loreen A
authors.initials: LA
authors.lastname: Herwaldt
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003428:Cross Infection / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007484:Iowa / Q000453:epidemiology; D008297:Male; D016106:Methicillin Resistance / Q000235:genetics*; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000150:complications* / Q000453:epidemiology / Q000635:transmission; D013290:Streptococcal Infections / Q000150:complications* / Q000453:epidemiology / Q000635:transmission; D020713:Vancomycin Resistance / Q000235:genetics*