Nosocomial Acinetobacter pneumonia: Treatment and prognostic factors in 356 cases

Respirology. 2016 Feb;21(2):363-9. doi: 10.1111/resp.12698. Epub 2015 Dec 3.

Abstract

Background and objective: Acinetobacter baumannii and A. baumannii/calcoaceticus complex are commonly encountered pathogens in nosocomial infections. This study aimed to evaluate the treatment and prognostic risk factors in nosocomial pneumonia caused by these microorganisms.

Methods: The study was conducted retrospectively in Uludag University Hospital and included 356 adult non-neutropenic patients with nosocomial pneumonia.

Results: Of the subjects, 94.9% (n = 338) had ventilator-associated pneumonia. The clinical response rate was 57.2%, the 14-day mortality 39.6% and the 30-day mortality 53.1%. The significant independent risk factors for the 30-day mortality were severe sepsis (OR, 2.60; 95% CI: 1.49-4.56; P = 0.001), septic shock (OR, 6.12; 95% CI: 2.75-13.64; P < 0.001), APACHE II score ≥ 20 (OR, 2.12; 95% CI: 1.28-3.50; P = 0.003) and empiric monotherapy (OR, 1.63; 95% CI: 1.00-2.64; P = 0.048). Multi-trauma (OR, 2.50; 95% CI: 1.11-5.68; P = 0.028) was found to be a protective factor. In patients with a clinical pulmonary infection score (CPIS) > 6 on the third day of treatment, both the 14- and 30-day mortality rates were high (P < 0.001, P < 0.001). Also, the 14- and 30-day mortality rates were significantly higher in the patients treated with empiric monotherapy compared with combination therapy (48/93 (51.6%)-46/123 (37.4%), P = 0.037 and 62/93 (66.7%)-65/123 (52.8%), P = 0.041, respectively) in pneumonia caused by imipenem-resistant strains.

Conclusion: Mortality rates were high in pneumonia caused by imipenem-resistant A. baumannii or A. baumannii/calcoaceticus complex. In the units with a high level of carbapenem resistance, antibiotic combinations should be considered for empiric therapy.

Keywords: Acinetobacter baumannii; colistin; nosocomial pneumonia; pneumonia; ventilator-associated pneumonia.

MeSH terms

  • Acinetobacter Infections / drug therapy*
  • Acinetobacter Infections / microbiology
  • Acinetobacter Infections / mortality
  • Acinetobacter baumannii*
  • Acinetobacter calcoaceticus*
  • Adult
  • Aged
  • Anti-Bacterial Agents / therapeutic use
  • Cross Infection / drug therapy
  • Cross Infection / microbiology
  • Cross Infection / mortality
  • Drug Resistance, Bacterial
  • Female
  • Humans
  • Imipenem / therapeutic use
  • Male
  • Middle Aged
  • Pneumonia, Bacterial / drug therapy*
  • Pneumonia, Bacterial / microbiology
  • Pneumonia, Bacterial / mortality
  • Pneumonia, Ventilator-Associated / drug therapy*
  • Pneumonia, Ventilator-Associated / microbiology
  • Pneumonia, Ventilator-Associated / mortality
  • Prognosis
  • Retrospective Studies
  • Risk Factors
  • Severity of Illness Index
  • Shock, Septic / mortality*

Substances

  • Anti-Bacterial Agents
  • Imipenem