title: Risk factors for prolonged carriage of vancomycin-resistant Enterococcus faecium among patients in intensive care units: a case-control study.
abstract: OBJECTIVE
  The aim of this study was to identify the risk factors for prolonged carriage of vancomycin-resistant Enterococcus faecium (VREF) in intensive care units (ICUs).
  
  
  METHODS
  A retrospective case-control study was performed in the ICUs of a university hospital in Korea from September 2006 to July 2009. VREF carriage was identified through weekly active surveillance rectal cultures. Clinical characteristics and the risk factors for VREF acquisition were compared between cases with prolonged VREF carriage (≥ 5 weeks, n = 58) and controls with shorter VREF carriage (<3 weeks, n = 36) in a multivariate logistic regression model. The effect of vancomycin consumption on vancomycin-resistant enterococci (VRE) colonization pressure was investigated using time-series analysis with an autoregressive error model.
  
  
  RESULTS
  Out of a total of 6327 rectal swab cultures examined, 1915 (30.3%) specimens from 266 patients were positive for VREF. The weekly VRE colonization pressure ranged from 0.77% to 42.42%. Vancomycin use after VREF acquisition significantly increased VREF carriage (adjusted odds ratio = 4.09; 95% confidence interval = 1.32-12.65). The case group had higher in-hospital mortality than the control group [21 (36.2%) versus 4 (11.1%), P = 0.007]. Increment of VRE colonization pressure was significantly associated with vancomycin consumption of 1week before (i.e. time t - 1) (P = 0.0028) and moderately associated with that of the corresponding week (i.e. time t) (P = 0.0595).
  
  
  CONCLUSIONS
  Vancomycin use in patients with VREF colonization might prolong the duration of carriage. Restriction of vancomycin use should be strengthened in these patients through infection control measures.
authors.affiliation: Division of Infectious Diseases, Korea University Medical Center, Seoul, Korea.
authors.forename: Young Kyung
authors.initials: YK
authors.lastname: Yoon
authors.forename: Seung Eun
authors.initials: SE
authors.lastname: Lee
authors.forename: Juneyoung
authors.initials: J
authors.lastname: Lee
authors.forename: Hyun Jeong
authors.initials: HJ
authors.lastname: Kim
authors.forename: Jeong Yeon
authors.initials: JY
authors.lastname: Kim
authors.forename: Dae Won
authors.initials: DW
authors.lastname: Park
authors.forename: Jang Wook
authors.initials: JW
authors.lastname: Sohn
authors.forename: Min Ja
authors.initials: MJ
authors.lastname: Kim
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D002353:Carrier State / Q000382:microbiology*; D016022:Case-Control Studies; D016984:Enterococcus faecium / Q000187:drug effects* / Q000302:isolation & purification; D005260:Female; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology*; D006801:Humans; D007362:Intensive Care Units; D007723:Korea; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D012007:Rectum / Q000382:microbiology; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D014640:Vancomycin / Q000627:therapeutic use; D020713:Vancomycin Resistance
chemical_list: D000900:Anti-Bacterial Agents; D014640:Vancomycin