Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Feb;149(2):208-215.
doi: 10.4103/ijmr.IJMR_172_18.

Molecular characterization of extended-spectrum β-lactamases among clinical isolates of Escherichia coli & Klebsiella pneumoniae: A multi-centric study from tertiary care hospitals in India

Vikas Gautam  1 , Anjana Thakur  1 , Megha Sharma  1 , Avinash Singh  1 , Shruti Bansal  1 , Aditi Sharma  1 , Arti Kapil  2 , Bimal Kumar Das  2 , Sujatha Sistla  3 , Subhash Chandra Parija  3 , Balaji Veeraraghavan  4 , John Antony Jude Prakash  4 , Kamini Walia  5 , V C Ohri  5 , Pallab Ray  1
Affiliations

Molecular characterization of extended-spectrum β-lactamases among clinical isolates of Escherichia coli & Klebsiella pneumoniae: A multi-centric study from tertiary care hospitals in India

Vikas Gautam et al. Indian J Med Res. 2019 Feb.

Abstract

Background & objectives: The increasing prevalence of extended-spectrum β-lactamases (ESBLs) has abated therapeutic options worldwide. This study was undertaken to investigate the molecular profile and resistance patterns of ESBLs among clinical isolates of Escherichia coli and Klebsiella pneumoniae at four tertiary care centres in India.

Methods: Clinical isolates of E. coli and K. pneumoniae were collected from the All India Institute of Medical Sciences (AIIMS), New Delhi; the Jawaharlal Institute of Postgraduate Medical Education & Research (JIPMER), Puducherry; Postgraduate Institute of Medical Education & Research (PGIMER), Chandigarh and Christian Medical College (CMC), Vellore, over one and a half year period. Antimicrobial susceptibility was determined by Kirby-Bauer disc diffusion method. ESBLs were confirmed phenotypically, and multiplex PCR was performed to identify genes for β-lactamases (blaTEM, blaSHV, blaOXA-1, blaCTXM-1, blaCTXM-2, blaCTXM-9 and blaCTXM-15).

Results: Among 341 E. coli isolates collected during the study period, 171 (50%) harboured blaTEM, 145 (43%) blaOXA-1,70 (21%) blaCTXM-1, 19 (6%) blaSHV and four (1%) harboured blaCTXM-2. Phenotypically, combined disc test detected ESBL production in 98/298 (33%) E. coli. Among 304 K. pneumoniae isolates, 115 (38%), 89 (29%), 83 (27%), 64 (21%) and two (0.6%) harboured blaTEM, blaOXA-1, blaCTXM-1, blaSHV and blaCTXM-2, respectively. Combined disc test (CDT) detected ESBL production in 42 per cent K. pneumoniae. Most of the blaCTXM-1positive isolates were also blaCTXM-15 positive. The carbapenem susceptibility ranged from 56 to 88 per cent for E. coli and from 20 to 61 per cent for K. pneumoniae. Antibiotic sensitivity patterns showed that colistin (CST) was the most sensitive drug for both E. coli (271/274, 99%) and K. pneumoniae (229/234, 98%).

Interpretation & conclusions: The prevalence of ESBL among four study centres varied, and blaTEM, blaOXA-1 and blaCTXM-15 were the most common genotypes in E. coli and K. pneumoniae isolates in India. The growing carbapenem resistance and emerging colistin resistance warrant the judicious use of these antimicrobials.

Keywords: Antibiotic sensitivity; Escherichia coli; Klebsiella pneumoniae; colistin resistance; extended-spectrum β; lactamases.

PubMed Disclaimer

Conflict of interest statement

None

References

    1. Bradford PA. Extended-spectrum beta-lactamases in the 21st century: Characterization, epidemiology, and detection of this important resistance threat. Clin Microbiol Rev. 2001;14:933–51. - PMC - PubMed
    1. Datta S, Wattal C, Goel N, Oberoi JK, Raveendran R, Prasad KJ. A ten year analysis of multi-drug resistant blood stream infections caused by Escherichia coli & Klebsiella pneumoniae in a tertiary care hospital. Indian J Med Res. 2012;135:907–12. - PMC - PubMed
    1. Sheng WH, Badal RE, Hsueh PR. SMART Program. Distribution of extended-spectrum β-lactamases, ampC β-lactamases, and carbapenemases among Enterobacteriaceae isolates causing intra-abdominal infections in the Asia-Pacific region: Results of the study for monitoring antimicrobial resistance trends (SMART) Antimicrob Agents Chemother. 2013;57:2981–8. - PMC - PubMed
    1. Ganguly NK, Arora NK, Chandy SJ, Fairoze MN, Gill JP, Gupta U, et al. Rationalizing antibiotic use to limit antibiotic resistance in India. Indian J Med Res. 2011;134:281–94. - PMC - PubMed
    1. Proceedings of the 16th international supplement (M100-S16) Wayne, Pa, USA: CLSI; 2006. Clinical and Laboratory Standards Institute. Performance standards for antimicrobial susceptibility testing.

MeSH terms