Antimicrobial Resistance Dynamics of Pseudomonas Aeruginosa in a Tertiary Care Hospital in Delhi

Background: Pseudomonas aeruginosa, non-fermenting gram-negative bacilli are a major cause of healthcare-associated infections. The rise in multidrug-resistant (MDR) strains globally has been associated with increased morbidity and mortality. In India, antimicrobial resistance (AMR) presents a significant challenge, necessitating effective policies and infection control measures. This study explores the resistance dynamics of P. aeruginosa in a tertiary care hospital, evaluating the findings in relation to the data from the Indian Council of Medical Research (ICMR).Methods: A total of 1,536 P. aeruginosa isolates from 31997 clinical samples of pus, wound, and burn swabs, respiratory specimens and body fluids submitted for routine culture were analyzed. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method. Blood, urine, cerebrospinal fluid (CSF), and stool were excluded.Results: P. aeruginosa accounted for 5th most frequent pathogen with prevalence declining from 15.7% (136/869) in 2020 to 7.7% (249/3236) in 2024. Among the isolates, 34.2% (525/1536) were susceptible to all tested antimicrobials, while 13.2% (203/1536) were MDR and 10.6% (163/1536) were extensively drug-resistant (XDR). Improved susceptibility was observed for piperacillin-tazobactam, carbapenems, aztreonam, and aminoglycosides, whereas, fluoroquinolones and monobactams showed persistently low susceptibility.Conclusion: Continuous monitoring of MDR pathogens like P. aeruginosa and their resistance dynamics are crucial for guiding treatment strategies and infection control measures.