Abstract

Pseudomonas aeruginosa is a Gram negative aerobic rod shaped bacterium and is an opportunistic pathogen that usually causes nosocomial infection in immunocompromised patient with various infections and affects normal healthy human as well. P. aeruginosa is also an omnipresent pathogen that can be inhabited in soil, water, vegetable, human and animal. Metallo-β-lactamases (MBL) producing P. aeruginosa are known to be resistant to almost the entire anti-pseudomonas agent via mechanism of low outer membrane permeability, β-lactamases synthesis and the efflux systems. This study was conducted to detect the potential of metallo-β-lactamases producing P. aeruginosa presence in water samples from various parts of Malaysia. In this study, 52 water samples were collected from various parts of Malaysia. These P. aeruginosa isolates were processed to these phenotypic methods, Hodge test which is used to detect the carbapenemase production, Imipenem- EDTA combined disc test (CDT). Imipenem-EDTA double disc synergy test (DDST) was used to determine metallo-beta-lactamases producing P. aeruginosa. Among 52 various sources of water samples, 13 water samples had positive P. aeruginosa isolates. 6 out of 13 positive isolates have shown positive results in Hodge test, CDT and DDST. All metallo-β-lactamases producing isolates are multi-drug resistant. Among water samples from various parts of Malaysia, MBL producing P. aeruginosa are highly found in Selangor followed by KL, and this P. aeruginosa are detected from drain followed by river. Although some advantages and disadvantages exist among these phenotyping methods, still CDT and DDST are optimal to detect MBL.

Key words: Metallo-β-lactamases, multi-drug resistance, phenotyping method, Pseudomonas aeruginosa.