Publication:

Detection and characterization of metallo-β-lactamases producing Pseudomonas aeruginosa clinical isolates at a tertiary care hospital of Bhopal, India

Background Carbapenems are very often used effectively against multidrug resistant strains of clinically troublesome pathogens like P. aeruginosa. But there is emerging threat of developing resistance against carbapenems mainly attributed to metallo-β-lactamases production which has proved to be a clinical disaster. Early detection and identification of MBL-producing strains is of crucial importance for the prevention of nosocomial dissemination through appropriate treatment, as well as the timely implementation of infection control measures. Therefore this study was undertaken for screening MBL production in clinical isolates of Pseudomonas aeruginosa.

Methods One hundred fifty consecutive clinical isolates of P. aeruginosa were subjected to susceptibility testing by disc-diffusion test as per CLSI 2014 guidelines. Imipenem resistant strains were then subjected to screening for MBL production by Imipenem- EDTA combined disc test and Imipenem-EDTA double-disc synergy test.

Results A total of 20 (13.3%) isolates of P. aeruginosa showed resistance to Imipenem out of which twelve (8%) were screened as MBL producers by CDT whereas 8 (5.3%) isolates gave positive result by DDST.

Conclusions Introduction of simple, cheap, reliable, reproducible screening tests for early detection and identification of MBL-producing organisms in routine diagnostics is of crucial importance for the prevention of nosocomial dissemination of MBL through appropriate treatment, as well as the timely implementation of effective infection control measures. Antibiotic Stewardship and strict antibiotic policy enforcing judicious use of antibiotics is the need of hour.