title: Mortality and the increase in length of stay attributable to the acquisition of Acinetobacter in critically ill patients.
abstract: OBJECTIVE
  To determine the impact of Acinetobacter baumannii (AB) acquisition in intensive care unit (ICU) patients on mortality and length of stay (LOS).
  
  
  METHODS
  Pairwise matched 1:1 case-control study.
  
  
  METHODS
  Medical-surgical ICU in a tertiary health care institution.
  
  
  METHODS
  During 16 months, all patients admitted to the ICU were eligible. Case patients were defined as every patient with an AB isolation 48 hrs after ICU admission. Control patients were retrospectively selected from ICU patients without any AB isolation, according to seven matching variables.
  
  
  RESULTS
  Attributable mortality and excess LOS in the ICU were measured. Eighty-seven patients were included, with 75 pairs successfully matched. Infection was defined in 48 patients (23 respiratory). The attributable mortality rate for AB acquisition was 30% (49% vs.19%) (95% confidence interval [CI] = 23%, 37%): 43% (CI = 34%, 52%) in patients with infection (58% vs.15%) and 53% (CI = 41%, 65%) in patients with respiratory infections (70% vs.17%). The estimated risk rates for death were 2.6 (CI = 1.6, 4.5; p < .001), 4.0 (CI = 1.9, 8.3; p < .001), and 4.0 (CI = 1.6, 10.2; p < .01), respectively. The attributable excess LOS was 13 days for both AB acquisition and infection (23 vs. 10 days; p < .001) and respiratory infections (23 vs. 10 days; p < .01). In noninfected patients, no significant excess of mortality was found (33% vs. 26%), but LOS increased in 15 days.
  
  
  CONCLUSIONS
  AB acquisition involved an excess LOS in ICU patients and increased risk of death, but the latter could be found only in patients with proven infection.
authors.affiliation: Intensive Care Unit, University Hospital Virgen del Rocío, Sevilla, Spain.
authors.forename: J L
authors.initials: JL
authors.lastname: García-Garmendia
authors.forename: C
authors.initials: C
authors.lastname: Ortiz-Leyba
authors.forename: J
authors.initials: J
authors.lastname: Garnacho-Montero
authors.forename: F J
authors.initials: FJ
authors.lastname: Jiménez-Jiménez
authors.forename: J
authors.initials: J
authors.lastname: Monterrubio-Villar
authors.forename: M
authors.initials: M
authors.lastname: Gili-Miner
mesh_terms: D000151:Acinetobacter Infections / Q000401:mortality*; D016022:Case-Control Studies; D016638:Critical Illness; D003428:Cross Infection / Q000401:mortality*; D004352:Drug Resistance, Microbial; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data*; D007902:Length of Stay; D008297:Male; D016555:Matched-Pair Analysis; D008875:Middle Aged; D012141:Respiratory Tract Infections / Q000382:microbiology / Q000401:mortality; D012306:Risk; D013030:Spain / Q000453:epidemiology