title: Mortality risk factors in patients with Acinetobacter baumannii ventilator: associated pneumonia.
abstract: OBJECTIVE
  Ventilator-associated pneumonia (VAP) caused by Acinetobacter baumannii has contributed to high mortality rate, prolonged stays in the intensive care unit, and the rapid development of antimicrobial resistance to commonly used antimicrobials. This study sought to determine predictors of mortality and carbapenem resistance for patients with A baumannii VAP.
  
  
  METHODS
  We retrospectively reviewed 541 adult patients with A baumannii pneumonia, who were admitted to a medical center between 2005 and 2007; of which 180 (33.3%) had been treated with mechanical ventilation. Of the 180 patients, 98 (54.4%) who survived were categorized as the survivor group, and 82 (45.6%) who died as the mortality group. Eighty-seven (48.3%) with imipenem-sensitive A baumannii VAP were categorized as the IS-AB group, and the remaining 93 (51.7%) with imipenem-resistant VAP as the IR-AB group.
  
  
  RESULTS
  Compared with the survivor group, the mortality group had significantly higher Charlson comorbidity index scores, and more neoplastic disease, other sites of infection, bloodstream infections, altered mental status, confusion, urea >7 mmol/L, respiratory rate >30/min, low blood pressure (systolic <90 mmHg or diastolic <60 mmHg), age >65 years (CURB-65) ≥ 3, creatinine > 1.6 mg/dL, C-reactive protein ≥ 100 mg/L, and imipenem resistance. The survivor group had more cases of tracheostomy and diabetes mellitus than the mortality group had. Compared with the IS-AB group, the IR-AB group had higher Charlson comorbidity index scores, longer stays before VAP onset, an increase in other sites of infection, white blood cell count <4/μL or >1.1 × 10(4)/μL, and higher hospital mortality rates.
  
  
  CONCLUSIONS
  Inadequate initial empiric antimicrobial therapy and higher disease severity scores, including CURB ≥ 3 and C-reactive protein ≥ 120 mg/L, were independent risk factors associated with higher mortality rates for A baumannii pneumonia. Length of stay before VAP and white blood cell count <4/μL or >1.1 × 10(4)/μL were independent risk factors for carbapenem resistance.
authors.affiliation: Division of Pulmonary & Critical Care Medicine, Department of Internal Medicine, Chang Gung Memorial Hospital- Kaohsiung Medical Center, Chang Gung University College of Medicine, Taiwan. ccwang52@adm.cgmh.org.tw
authors.forename: Huang-Chih
authors.initials: HC
authors.lastname: Chang
authors.forename: Yung-Che
authors.initials: YC
authors.lastname: Chen
authors.forename: Meng-Chih
authors.initials: MC
authors.lastname: Lin
authors.forename: Shih-Feng
authors.initials: SF
authors.lastname: Liu
authors.forename: Yu-Hsiu
authors.initials: YH
authors.lastname: Chung
authors.forename: Mao-Chang
authors.initials: MC
authors.lastname: Su
authors.forename: Wen-Feng
authors.initials: WF
authors.lastname: Fang
authors.forename: Chia-Chen
authors.initials: CC
authors.lastname: Tseng
authors.forename: Chien-Hao
authors.initials: CH
authors.lastname: Lie
authors.forename: Kuo-Tung
authors.initials: KT
authors.lastname: Huang
authors.forename: Chin-Chou
authors.initials: CC
authors.lastname: Wang
mesh_terms: D040981:Acinetobacter baumannii / Q000302:isolation & purification*; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D053717:Pneumonia, Ventilator-Associated / Q000188:drug therapy / Q000209:etiology* / Q000401:mortality; D012189:Retrospective Studies; D012307:Risk Factors