Impact of multi-drug-resistant Acinetobacter baumannii on clinical outcomes

  • A. Abbo
  • Y. Carmeli
  • S. Navon-Venezia
  • Y. Siegman-Igra
  • M. J. Schwaber


We conducted a retrospective matched cohort study to examine the impact of isolation of multi-drug-resistant (MDR) Acinetobacter baumannii on patient outcomes. Cases from whom MDR A. baumannii was isolated in a clinical culture (n = 118) were compared with controls from whom MDR A. baumannii was not isolated (n = 118). Cases and controls were matched according to ward, calendar month of hospitalization, and duration of hospitalization before culture. The following outcomes were compared in multivariable analysis: in-hospital mortality, length of stay, need for mechanical ventilation, and functional status at discharge. MDR A. baumannii was determined to be a pathogen in 72% of cases. In 36% of cases, the patient died, versus 21% of controls (odds ratio [OR] 2.21, 95% confidence interval [CI] 1.17–4.16, P = 0.014). Median length of stay for surviving cases was 17 days, versus 11 for surviving controls (multiplicative effect 1.55, 95% CI 0.99–2.44, P = 0.057). Fifty-two percent of cases required mechanical ventilation, versus 25% of controls (OR 3.72, 95% CI 1.91–7.25, P<0.001); 60% of surviving cases were discharged with reduced functional status, versus 38% of controls (OR 4.4, 95% CI 1.66–11.61, P = 0.003). In multivariable analysis, clinical isolation of MDR A. baumannii remained a significant predictor of mortality (OR 6.23, 95% CI 1.31–29.5, P = 0.021), need for mechanical ventilation (OR 7.34, 95% CI 2.24–24.0, P<0.001), and reduced functional status on discharge (OR 7.93, 95% CI 1.1–56.85, P = 0.039). Thus, MDR A. baumannii acquisition is associated with severe adverse outcomes, including increased mortality, need for mechanical ventilation, and reduced functional status.


Mechanical Ventilation Colistin Foley Catheter Acinetobacter Baumannii Resistant Organism 
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This study was funded by a grant from the United States-Israel Binational Science Foundation. The Foundation had no role in the design or conduct of any aspect of the study.


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • A. Abbo
    • 1
  • Y. Carmeli
    • 1
  • S. Navon-Venezia
    • 1
  • Y. Siegman-Igra
    • 2
  • M. J. Schwaber
    • 1
  1. 1.Division of EpidemiologyTel Aviv Sourasky Medical CenterTel AvivIsrael
  2. 2.Division of Infectious DiseasesTel Aviv Sourasky Medical CenterTel AvivIsrael

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