METALLO-B-LACTAMASE PHENOTYPIC AND MOLECULAR DETECTION IN IMIPENEM-RESISTANT GRAM-NEGATIVE BACILLI FROM A TERTIARY CARE HOSPITAL IN CENTRAL INDIA
Main Article Content
Keywords
MBL, PCR, EDS, MHT
Abstract
Background: The ability of metallo-β-lactamase (MBL)-producing Gram-negative bacilli to hydrolyze carbapenems, which are frequently employed as last-resort antibiotics, poses a significant therapeutic problem. In India's tertiary care facilities, where carbapenem resistance is rising, particularly among non-fermenters, this issue is very serious.
AIM- In a tertiary care hospital in Central India, the current study sought to ascertain the frequency of carbapenem-resistant Gram-negative bacilli and to assess phenotypic and genetic techniques for MBL production detection.
Materials and Methods: The Department of Microbiology at the Index Medical College Hospital and Research Center in Indore carried out a cross-sectional observational study. Standard microbiological methods were used to process 900 clinical samples. Conventional biochemical techniques were used to identify isolates that were gram-negative. The Kirby-Bauer method was used to test for antimicrobial susceptibility. The Modified Hodge Test (MHT) and EDTA Disc Synergy (EDS) were used to screen isolates that were resistant to carbapenem for the generation of MBL. PCR was used to detect the blaIMP gene molecularly.
Results: Gram-negative bacteria were found in 524 (58.2%) of the 900 samples; 231 (25.7%) of them were resistant to carbapenem. The most common resistant species were Acinetobacter baumannii (48.0%) and Klebsiella pneumoniae (38.6%). EDS and MHT positivity rates for phenotypic MBL identification were 28.1% and 24.2%, respectively. 7.2% of carbapenem-resistant isolates had the blaIMP gene identified by PCR. Male patients and older individuals showed greater resistance.
Conclusion: In this context, carbapenem resistance and MBL generation are serious issues. While molecular techniques offer supporting data, phenotypic methods are still useful for routine screening. Effective surveillance, infection control, and antimicrobial stewardship need the combined application of both strategies.
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Neha Rani
PhD Scholar, Department of Microbiology, Index Medical College, Hospital & Research Centre, Indore, India. (Malwanchal University) Email- [email protected]
Dr. Harshada Shah
Research supervisor, Department of Microbiology, Index Medical College, Hospital & Research Centre, Indore (M.P)India. (Malwanchal University) [email protected]
Hemant Kumar
PhD Scholar, Department of Microbiology, Index Medical College, Hospital & Research Centre, Indore, (M.P) India (Malwanchal University) Email – [email protected]
