DETECTION OF ANTIBIOTIC RESISTANCE IN Pseudomonas aeruginosa ISOLATES WITH SPECIAL REFERENCE TO METALLO Β-LACTAMASES FROM A TERTIARY CARE HOSPITAL IN WESTERN INDIA

Background: Pseudomonas aeruginosa is an important cause of morbidity and mortality in hospitalised patients. The prevalence of multidrug resistant Pseudomonas aeruginosa strains including resistance to Carbapenems has been an increasing cause of concern. Hence this study was undertaken to know the resistance pattern of Pseudomonas aeruginosa to various anti-pseudomonal antibiotics and also to detect Metallo β lactamase production in them.Methodology: Pseudomonas aeruginosa isolates from various clinical samples were tested. Antibiotic sensitivity testing was carried out by Kirby- Bauer method according to CLSI guidelines and detection of Metallo-β-lactamase production was carried out by Imipenem EDTA combined disc method.Results: 125 clinical isolates of Pseudomonas aeruginosa were tested. The resistance pattern to various antibiotics were- Amikacin (18.4%), Gentamycin (63.2%), Netilmycin (32.8%), Ceftazidime (74.4%), Ciprofloxacin (60%), Imipenem (21.6%), Piperacillin (54.4%), Piperacillin+tazobactum (45.6%), Polymyxin-B (20%), Colistin (15.2%), Tobramycin (55.2%), Levofloxacin (41.6%), Carbenicillin (51.2%). 21.6% of the isolates were resistant to Imipenem and 6 out of 27 i.e 22.2% were positive for Metallo β lactamase production. Conclusions: Amikacin, Carbapenems, Colistin and Polymyxin are the main drugs to treat multidrug resistant Pseudomonas aeruginosa and Metallo β lactamase detection has to be done to identify resistance to Carbapenems.