Mortality from acinetobacter infections as compared to other infections among critically ill patients in South India: A prospective cohort study.

Background: Acinetobacter baumannii has become a common pathogen causing hospital-acquired infections (HAIs). Although acquiring any nosocomial infection is associated with increased mortality, we do not know if the acquisition of Acinetobacter infection confers a worse prognosis as compared to non-Acinetobacter-related HAI. The aim of the current study is to compare the clinical outcomes of ventilator-associated pneumonia (VAP) and central line associated blood stream infections (CLABSIs) caused by A. baumannii with those caused by other bacterial pathogens.

Materials and Methods: This prospective cohort study was conducted among critically ill adults admitted to a tertiary care hospital in South India from January 2013 to June 2014. We enrolled patients who developed new-onset fever ≥48 h after admission and fulfilled pre-specified criteria for VAP or CLABSI. The patients were followed up until the primary outcomes of death or hospital discharge.

Results: During the study period, 4047 patients were admitted in the intensive care units, among which 129 eligible HAI events were analysed. Of these, 95 (73.6%) were VAP, 34 (26.4%) were CLABSI, 78 (60.4%) were A. baumannii-related HAI (AR-HAI) and 51 (39.6%) were non-A. baumannii-related HAI (NAR-HAI). Mortality among AR-HAI was 57.6% compared to 39.2% in NAR-HAI (P = 0.04) which on multivariate analysis did not achieve statistical significance, although the trend persisted (odds ratio [OR] = 4.2, 95% confidence interval [CI]: 0.95-18.4, P = 0.06). The acquisition of VAP due to A. baumannii was associated with poor ventilator outcomes even after adjusting for confounders (adjusted OR = 3.5, 95% CI: 1.07-11.6, P = 0.04).

Conclusion: In our cohort of critically ill adults with VAP and CLABSI, AR-HAI was associated with poor ventilator outcomes and a trend towards higher mortality. These findings add to the evidence suggesting that A. baumannii is a dangerous pathogen, perhaps even more so than others.