• Shivani Saxena King George’s Medical University
  • Gopa Banerjee Departments of Microbiology, King George’s Medical University, Lucknow (UP) India
  • Rajiv Garg King George’s Medical University
  • Mastan Singh King George’s Medical University
  • S. K Verma King George’s Medical University
  • R. A. S. Kushwaha King George’s Medical University


Objectives: The present study was undertaken to determine the prevalence of multi drug resistant (MDR) and multiple β-lactamase producing Pseudomonas aeruginosa isolates in lower respiratory tract infection (LRTI) patients at a tertiary care hospital in India.

Methods: A total of 80 consecutive, non-duplicate isolates of P. aeruginosa were studied for the presence of class A or B β-lactamase. Antibiotic susceptibility tests and PCR amplification of genes encoding class A (PER-1 and CTX-M 1, 2, 9) and class B β-lactamases (blaVIM-2, blaIMP-1 and blaSIM-1) were performed.

Results: Out of 80 P. aeruginosa isolates, 65% (52/80) of the isolates were MDR with 34 being Metallo-β-lactamase (MBL) producers, 23 were extended spectrum β-lactamase (ESBL) producers and 21 were positive for AmpC production. The cross-class resistance rates to other antibiotics was significantly higher in class A and B β-lactamase producers than in non-producers (P<0.05 for fluoroquinolone, aztreonam, ceftazidime and meropenem). Combined disk test (CDT) for MBL highest sensitivity and specificity compared to PCR. Combined disk method (CDM) for ESBL co-related well with PCR (sensitivity and specificity).

Conclusion: This study reports the validation of a simple and accurate MBL and ESBL detection method which can be easily integrated into the daily routine of a clinical laboratory.


Keywords: Pseudomonas aeruginosa, Beta-lactamase genes, MDR


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How to Cite
Saxena, S., G. Banerjee, R. Garg, M. Singh, S. K. Verma, and R. A. S. Kushwaha. “ESBL, MBL AND AMP C-β LACTAMASES PRODUCED BY SUPERBUGS: AN EMERGING THREAT TO CLINICAL THERAPEUTICS”. International Journal of Pharmacy and Pharmaceutical Sciences, Vol. 7, no. 9, July 2015, pp. 353-6,
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