title: Prognostic factors associated with mortality of drug-resistant Acinetobacter baumannii ventilator-associated pneumonia.
abstract: BACKGROUND
  Ventilator-associated pneumonia (VAP) caused by drug-resistant Acinetobacter baumannii is associated with high mortality in critically ill patients. We identified the prognostic factors of 30-day mortality in patients with VAP caused by drug-resistant A. baumannii and compared survival outcomes among multidrug-resistant (MDR), extensively drug-resistant (XDR) and pandrug-resistant (PDR) A. baumannii VAP.
  
  
  METHODS
  A retrospective cohort study was conducted in the Medical Intensive Care Unit at Chiang Mai University Hospital, Thailand. All adult patients diagnosed with A. baumannii VAP between 2005 and 2011 were eligible. Univariable and multivariable Cox's proportional hazards regression were performed to identify the prognostic factors of 30-day mortality.
  
  
  RESULTS
  A total of 337 patients with microbiologically confirmed A. baumannii VAP were included. The proportion of drug-sensitive (DS), MDR, XDR, and PDR A. baumannii were 9.8%, 21.4%, 65.3%, and 3.6%, respectively. The 30-day mortality rates were 21.2%, 31.9%, 56.8%, and 66.7%, respectively. The independent prognostic factors were SOFA score >5 (hazard ratio (HR) = 3.33, 95% confidence interval (CI) 1.94-5.72, P < 0.001), presence of septic shock (HR = 2.66, 95% CI 1.71-4.12, P < 0.001), Simplified Acute Physiology Score (SAPS) II >45 (HR = 1.58, 95% CI 1.01-2.46, P = 0.045), and inappropriate initial antibiotic treatment (HR = 1.53, 95% CI 1.08-2.20, P = 0.016).
  
  
  CONCLUSIONS
  Drug-resistant A. baumannii, particularly XDR and PDR, was associated with a high mortality rate. Septic shock, high SAPS II, high SOFA score, and inappropriate initial antibiotic treatment were independent prognostic factors for 30-day mortality.
authors.affiliation: Division of Pulmonary, Critical Care and Allergy, Department of Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200 Thailand.
authors.forename: Juthamas
authors.initials: J
authors.lastname: Inchai
authors.affiliation: Division of Pulmonary, Critical Care and Allergy, Department of Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200 Thailand.
authors.forename: Chaicharn
authors.initials: C
authors.lastname: Pothirat
authors.affiliation: Division of Pulmonary, Critical Care and Allergy, Department of Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200 Thailand.
authors.forename: Chaiwat
authors.initials: C
authors.lastname: Bumroongkit
authors.affiliation: Division of Pulmonary, Critical Care and Allergy, Department of Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200 Thailand.
authors.forename: Atikun
authors.initials: A
authors.lastname: Limsukon
authors.affiliation: Department of Medicine, Nakornping Hospital, Chiang Mai, Thailand.
authors.forename: Weerayut
authors.initials: W
authors.lastname: Khositsakulchai
authors.affiliation: Division of Pulmonary, Critical Care and Allergy, Department of Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200 Thailand.
authors.forename: Chalerm
authors.initials: C
authors.lastname: Liwsrisakun
keywords: Extensively drug-resistant A. baumannii; Mortality; Pandrug-resistant A. baumannii; Prognostic factor; Ventilator-associated pneumonia