Predictors of mortality in patients with Gram-Negative Bacilli (GNB) blood stream infections (BSI): multicentre data from India.

Background: This study was done with objectives of determining the predictors of mortality in patients with Gram-Negative Bacilli (GNB) Blood stream Infection (BSI) along with estimating mortality attributable to carbapenem resistance (CR).

Methods: In this prospective cohort study (January 2023-September 2024), done in 3 tertiary care centres in India, patients found to have mono-microbial GNB BSI were included. Primary outcome was crude mortality at day 30 of onset of BSI.

Results: Out of 604 patients, mortality at day 30 happened in 140 (23.2%) patients. Intergroup analysis between patients alive (n = 464) and dead (n = 140) at day 30 revealed that lower age (p = 0.014), higher Sequential Organ Failure Assessment Score (SOFA) score (p < 0.001), higher Pitts Bacteraemia score (p < 0.001), acquisition of BSI in hospital (p = 0.003) and CR in Enterobacterales (Escherichia coli & Klebsiella pneumoniae[CRKP] and Acinetobacter baumannii (CRAB) and DTR (defined as non-susceptibility to carbapenems, β-lactam-β-lactamase inhibitor combinations, and fluoroquinolones) in Pseudomonas aeroginosa [DTR-PA] (CR E. coli, p = 0.034; CRKP, p = 0.012; CRAB, p < 0.001; DTR-PA, p < 0.001) was associated with higher mortality. On multivariate logistic regression analysis, higher SOFA score (p < 0.001) and BSI due to DTR-PA (p = .006) and CRAB (p= .017) were found to be independent predictors of mortality. Attributable mortality of CR in E. coli and K. pneumoniae and DTR in PA was 7.32, 8.43 and 52.4% respectively.

Conclusion: We did not find CR as a major contributing factor for death among patients with BSI due to Enterobacterales in our study cohort.