Recent Trends in Antimicrobial Resistance Patterns of Acinetobacter baumannii in Tertiary Care Hospital in Guwahati

Objectives: The rapid emergence of Acinetobacter baumannii has become a major challenge in tertiary care settings, particularly in regions with high antimicrobial usage. This study aimed to determine the antimicrobial susceptibility profile and resistance burden of A. baumannii isolates from a tertiary care hospital in Guwahati, Assam. Material and Methods: A 102 non-duplicate A. baumannii isolates were collected from tracheal aspirates, blood, urine, sputum, pus, and other body fluids from both outpatient and inpatient departments. Identification was performed using conventional methods and further by the VITEK2 Compact system. Antimicrobial susceptibility testing was carried out using the Kirby-Bauer disk diffusion method in accordance with the Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: A high prevalence of resistance was observed across most antimicrobial classes, including β-lactam/β-lactamase inhibitor combinations, cephalosporins, carbapenems, aminoglycosides, and fluoroquinolones. Carbapenem resistance ranged from 77 to 78%. Overall, 98% of isolates were classified as multidrug resistance (MDR). In contrast, relatively higher susceptibility was observed for minocycline. Conclusion: The study demonstrates a high burden of MDR A. baumannii with widespread resistance across multiple antibiotic classes and limited remaining therapeutic options. This emphasizes the urgent need for robust antimicrobial stewardship, continuous surveillance, and strengthened infection control strategies to mitigate the spread of resistant strains.