PHENOTYPIC AND MOLECULAR DETECTION OF CARBAPENEMASE NEW DELHI METALLO BETA LACTAMASE-1 (NDM-1) GENE AMONG PSEUDOMONAS AERUGINOSA FROM VARIOUS CLINICAL ISOLATES

Pseudomonas aeruginosa is an opportunistic pathogen which acquires resistance to antibiotics such as carbapenems and cefepime. Information regarding (NDM-1) gene producing Pseudomonas aeruginosa is available, but data regarding their degree of infection and percentage in hospital settings are scarce. Hence, this study was carried out to determine the occurrence of blaNDM-1 gene among clinical isolates of multidrug-resistant Pseudomonas aeruginosa in a tertiary care hospital in Chennai, Tamil Nadu, India. A total of 126 isolates of P. aeruginosa isolated from various clinical samples were evaluated for carbapenem resistance and MBL production. In the present study it was found that majority of isolates (39.7%) were resistant to imipenem followed by ertapenem (35.9%) and doripenem (24.3%). A total of 31/78 (39.7%) isolates of P. aeruginosa were resistant to one or both carbapenems (imipenem and ertapenem) used in the screening test. Out of 78 isolates, 27 (34.6%) and 25 (32.1%) isolates were MHT positive and MBL producers by Modified Hodge Test (MHT) and MBL E-Strip test respectively and Out of 25 MBL positive isolates, 7 (28%) isolates were positive, and 18 (72%) were negative for NDM-1 gene production. In this study prevalence of plasmid encoding NDM-1 gene was noted in Multidrug-resistant Pseudomonas aeruginosa. Screening of Pseudomonas aeruginosa along with routine antimicrobial susceptibility testing, Phenotypic and molecular screening should also be carried out regularly to reflect the proper number of metallo-beta-lactamase producers.