Metallo-β-lactamase-producing Pseudomonas aeruginosa Isolates from Two Tertiary Care Centres in a District of Nepal: A Descriptive Cross-sectional Study.

Introduction: Pseudomonas aeruginosa isolates producing metallo-β-lactamase have caused nosocomial outbreaks, severe infections, and ineffective carbapenem therapy worldwide since 1991. Due to their prevalence, hospital infection control techniques are difficult. This study aimed to find out the prevalence of metallo-β-lactamase among P. aeruginosa isolates from two tertiary care hospitals in Kathmandu.

Methods: A descriptive cross-sectional study was conducted at the Department of Microbiology and Department of Pathology of two tertiary care centres in Kathmandu from 7 December 2021 to 6 April 2023, after receiving ethical approval from the Ethical Review Board. Isolated strains were identified and tested for antibiotic susceptibility by modified Kirby-Bauer Methods. Metallo-β-lactamase presence was confirmed using an imipenem-imipenem/ ethylenediaminetetraacetic acid disc. A convenience sampling method was used. The point estimate was calculated at 95% Confidence Interval.

Results: Among 255, Pseudomanas aeruginosa isolates, the distribution of metallo-β-lactamase-producing Pseudomanas aeruginosa was 103 (40.39%) (34.32-46.69 at 95% Confidence Interval). Multidrug resistance categories included multidrug resistance 74 (71.80%), extensively drug resistance 32 (31.10%), P. aeruginosa difficult-to-treat 16 (15.53%) and carbapenem-resistant P. aeruginosa was determined to be 82 (79.60%).

Conclusions: The study found a high prevalence of metallo-β-lactamase-producing Pseudomanas aeruginosa isolates, requiring early identification, infection control measures, and an all-inclusive antimicrobial therapy protocol to reduce their spread in medical settings.