Prevalence of New Delhi metallo-β-lactamase-1 in Pseudomonas aeruginosa and its antimicrobial resistance profile in hospitalized patients in a tertiary care hospital setup

Abstract

BACKGROUND: Pseudomonas aeruginosa is one of the most common causes of nosocomial infections. Carbapenems are widely used for the treatment of this microorganism, but nowadays, increasing number of carbapenem-resistant P. aeruginosa (CRPA) isolates are increasing which further lead to treatment failure due to associated multidrug resistance. AIM: The present study was done to determine the prevalence of New Delhi metallo-β-lactamase-1 (bla NDM-1) in P. aeruginosa in hospitalized patients in a tertiary care setup. SETTINGS AND DESIGN: The study was conducted in the department of microbiology with the tertiary care hospital settings. It was a prospective cross-sectional observational study conducted from June 2014 to December 2014. MATERIALS AND METHODS: Antibiotic susceptibility test was performed using Kirby–Bauer disc diffusion method for screening of the isolates. P. aeruginosa isolates with the zone diameter of carbapenems ≤18 mm were considered as carbapenemase producers. Metallo-beta-lactamases (MBL) detection was done using imipenem- ethylenediaminetetraacetic acid double-disc synergy test. NDM-1 gene in P. aeruginosa was identified using conventional polymerase chain reaction. STATISTICAL ANALYSIS USED: Chi-square test was used to analyze the data and P RESULTS: Out of 460 P. aeruginosa, 74 (16.08%) isolates were CRPA. A total of 61 (13.2%) MBL-producing P. aeruginosa were isolated, and bla NDM-1 gene was detected in 18 (3.91%) P. aeruginosa isolates. CONCLUSION: The study showed increasing multidrug resistance among CRPA compared to carbapenem-sensitive P. aeruginosa. It also determined increasing prevalence of bla NDM-1 in P. aeruginosa isolates. It is emphasized to timely identify these pathogens and treat with proper antibiotics to reduce morbidity and mortality.