Pseudomonas aeruginosa is a Gram-negative aerobic bacillus ubiquitously distributed across environmental and healthcare niches. It functions as a highly effective opportunistic pathogen, particularly posing severe risks in hospital settings, intensive care units, and through hospital-acquired (nosocomial) infections. This study was conducted on P. aeruginosa strains isolated from various clinical specimens to evaluate the institutional prevalence of infection and determine their current antibiotic drug susceptibility and multidrug resistance patterns. Out of 100 clinical diagnostic samples processed over a six-month period, 30 samples returned positive microbial cultures, from which 9 isolates were definitively identified as P. aeruginosa. The highest infection rates were recorded in patients aged 70–79 years (33.33%), with sputum (33.33%) and pus aspirates (26.60%) being the predominant isolation sites. Antimicrobial susceptibility testing via the Kirby-Bauer disc diffusion method demonstrated that Imipenem exhibited the strongest therapeutic profile with the lowest resistance rate (11.25%), whereas high resistance levels were observed for Aztreonam (72.50%), Ceftazidime (71.25%), Gentamicin (70.00%), and Ciprofloxacin (65.00%). Continuous local epidemiological monitoring, routine screening, and strict institutional antibiotic stewardship policies are imperative to preserve carbapenem efficacy and mitigate nosocomial transmission.

Keywords: Pseudomonas aeruginosa, Antibiotic Susceptibility, Nosocomial Infection, Multidrug Resistance, Tertiary Care Centre, Carbapenems, Opportunistic Pathogen, Phenotypic Identification, Antimicrobial Stewardship, Intensive Care Unit, Microscopic Profiling, Clinical Microbiology.

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Source of Funding:

This study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Competing Interests Statement:

The authors declare that they have no competing interests related to this work.

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The authors declare that they consented to the publication of this study.

Authors' contributions:

All the authors made an equal contribution in the Conception and design of the work, Data collection, Drafting the article, and Critical revision of the article.

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Authors are willing to share data and material on request.

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Not applicable for this study.

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Not applicable for this study.

Informed Consent:

Not applicable for this study.

Acknowledgement:

Authors acknowledge the support and hard work from all those who helped in this study.