Efficacy of adjunctive nebulized colistin in critically ill patients with nosocomial carbapenem-resistant Gram-negative bacterial pneumonia: a multi-centre observational study

Clin Microbiol Infect. 2021 Oct;27(10):1465-1473. doi: 10.1016/j.cmi.2021.01.020. Epub 2021 Feb 1.

Abstract

Objectives: To investigate the association between adjunctive nebulized colistin and treatment outcomes in critically ill patients with nosocomial carbapenem-resistant Gram-negative bacterial (CR-GNB) pneumonia.

Methods: This retrospective, multi-centre, cohort study included individuals admitted to the intensive care unit with nosocomial pneumonia caused by colistin-susceptible CR-GNB. Enrolled patients were divided into groups with/without nebulized colistin as adjunct to at least one effective intravenous antibiotic. Propensity score matching was performed in the original cohort (model 1) and a time-window bias-adjusted cohort (model 2). The association between adjunctive nebulized colistin and treatment outcomes was analysed.

Results: In total, 181 and 326 patients treated with and without nebulized colistin, respectively, were enrolled for analysis. The day 14 clinical failure rate and mortality rate were 41.4% (75/181) versus 46% (150/326), and 14.9% (27/181) versus 21.8% (71/326), respectively. In the propensity score-matching analysis, patients with nebulized colistin had lower day 14 clinical failure rates (model 1: 41% (68/166) versus 54.2% (90/166), p 0.016; model 2: 35.3% (41/116) versus 56.9% (66/116), p 0.001). On multivariate analysis, nebulized colistin was an independent factor associated with fewer day 14 clinical failures (model 1: adjusted odds ratio (aOR) 0.59, 95% CI 0.37-0.92; model 2: aOR 0.37, 95% CI 0.21-0.65). Nebulized colistin was not associated independently with a lower 14-day mortality rate in the time-dependent analysis in both models 1 and 2.

Conclusions: Adjunctive nebulized colistin was associated with lower day 14 clinical failure rate, but not lower 14-day mortality rate, in critically ill patients with nosocomial pneumonia caused by colistin-susceptible CR-GNB.

Keywords: Carbapenem-resistant Gram-negative bacteria; Clinical failure; Colistin; Mortality; Nosocomial pneumonia.

Publication types

  • Multicenter Study
  • Observational Study

MeSH terms

  • Anti-Bacterial Agents / therapeutic use*
  • Carbapenems / therapeutic use
  • Colistin / therapeutic use*
  • Critical Illness
  • Drug Resistance, Multiple, Bacterial
  • Gram-Negative Bacterial Infections* / drug therapy
  • Gram-Negative Bacterial Infections* / mortality
  • Healthcare-Associated Pneumonia* / drug therapy
  • Healthcare-Associated Pneumonia* / mortality
  • Humans
  • Pneumonia, Bacterial* / drug therapy
  • Pneumonia, Bacterial* / mortality
  • Retrospective Studies
  • Treatment Outcome

Substances

  • Anti-Bacterial Agents
  • Carbapenems
  • Colistin