Colistin resistance among the Gram-negative nosocomial pathogens in India: a systematic review and meta-analysis.

The rapid rise of nosocomial infections and the growing ineffectiveness of frontline antibiotics against Gram-negative bacteria (GNB) have put the healthcare sector under unprecedented stress. In this scenario, colistin, an antibiotic of the polymyxin class, has become the last resort treatment option. However, the unrestricted use of colistin in the preceding decades has led to the emergence of colistin-resistant (Col^R) bacterial strains. Unfortunately, comprehensive data on the prevalence of Col^R nosocomial pathogens in India are scarce. This study was conducted to address this information gap. A systematic review and meta-analysis were conducted to determine the prevalence of Col^R among the nosocomial GNB species in India and their geographical distribution. A systematic search of the online databases was performed and eligible studies meeting the inclusion criteria were used for qualitative synthesis. The combined event rate and 95% confidence interval were estimated using a forest plot with a random-effect model. Cochrane Q statistics and I² statistics were used to detect possible heterogeneity. From a total of 1865 retrieved records from 4 databases, 33 studies were included in the study. Among the most common nosocomial pathogens, Klebsiella pneumoniae showed a rate of Col^R at 16.1% (95% CI: 10.1 to 24.6), followed by Pseudomonas aeruginosa (13.3%) (95% CI: 9.1 to 19.2), Acinetobacter baumannii (10%) (95% CI: 7.5 to 13.2), and Escherichia coli (7.8%) (95% CI: 5.3 to 11.2). Interestingly, our analysis revealed that Enterobacter cloacae have the highest rate of Col^R at 27.9% (95% CI: 12.7 to 50.9). The results indicate that the prevalence of Col^R nosocomial pathogens vary among regions and over time; however, continuous monitoring, and sustained efforts are crucial to ensure the effectiveness of colistin antibiotic.