title: Risk factors for multi-drug resistant Acinetobacter baumannii bacteremia in patients with colonization in the intensive care unit.
abstract: BACKGROUND
  Epidemic outbreaks of multi-drug resistant (MDR) Acinetobacter baumannii (AB) in intensive care units (ICUs) are increasing. The incidence of MDR AB bacteremia, which develops as a result of colonization, is increasing through widespread dissemination of the pathogen, and further colonization. We sought to determine risk factors for MDR AB bacteremia in patients colonized with MDR AB in the ICU.
  
  
  METHODS
  We conducted a retrospective, observational study of 200 patients colonized with MDR AB in the ICU at Severance Hospital, South Korea during the outbreak period between January 2008 and December 2009.
  
  
  RESULTS
  Of the 200 patients colonized with MDR AB, 108 developed MDR AB bacteremia, and 92 did not. APACHE II scores were higher in bacteremic than non-bacteremic patients at the time of ICU admission and colonization (24.0 vs. 21.6; P = 0.035, 22.9 vs. 16.8; P < 0.001, respectively). There was no difference between the two groups in the duration of time from ICU admission to colonization (7.1 vs. 7.2 days; P = 0.923), but the duration of time at risk was shorter in bacteremic patients (12.1 vs. 6.0 days; P = 0.016). A recent invasive procedure was a significant risk factor for development of bacteremia (odds ratio = 3.85; 95% CI 1.45-10.24; P = 0.007). Multivariate analysis indicated infection and respiratory failure at the time of ICU admission, maintenance of mechanical ventilation, maintenance of endotracheal tube instead of switching to a tracheostomy, recent central venous catheter insertion, bacteremia caused by other microorganism after colonization by MDR AB, and prior antimicrobial therapy, were significant risk factors for MDR AB bacteremia.
  
  
  CONCLUSIONS
  Patients in the ICU, colonized with MDR AB, should be considered for minimizing invasive procedures and early removal of the invasive devices to prevent development of MDR AB bacteremia.
authors.affiliation: Division of Pulmonology, Institute of Chest Disease, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Ji Ye
authors.initials: JY
authors.lastname: Jung
authors.forename: Moo Suk
authors.initials: MS
authors.lastname: Park
authors.forename: Song Ee
authors.initials: SE
authors.lastname: Kim
authors.forename: Byung Hoon
authors.initials: BH
authors.lastname: Park
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Son
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Kim
authors.forename: Joo Eun
authors.initials: JE
authors.lastname: Lim
authors.forename: Sang Kook
authors.initials: SK
authors.lastname: Lee
authors.forename: Sang Hoon
authors.initials: SH
authors.lastname: Lee
authors.forename: Kyung Jong
authors.initials: KJ
authors.lastname: Lee
authors.forename: Young Ae
authors.initials: YA
authors.lastname: Kang
authors.forename: Se Kyu
authors.initials: SK
authors.lastname: Kim
authors.forename: Joon
authors.initials: J
authors.lastname: Chang
authors.forename: Young Sam
authors.initials: YS
authors.lastname: Kim
mesh_terms: D000151:Acinetobacter Infections / Q000453:epidemiology* / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000187:drug effects* / Q000302:isolation & purification; D000368:Aged; D016470:Bacteremia / Q000453:epidemiology* / Q000382:microbiology; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors