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bioRxiv · 10.1101/2020.11.29.403220

Detection of NDM-1, VIM-1 and AIM-type Metallo-beta-lactamase genes in Gram-negative bacteria isolated from clinical samples in Tamil Nadu

Manohar, P.·Joseph, A.·Nair, K. B.·AnuPriya, P.·Mani, S. S.·Varsha, V.·Ramesh, N.
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Abstract

The distribution of carbapenem-resistant Gram-negative bacteria has become an increasing public health concern in India. The aim of this study was to investigate the prevalence of carbapenem-resistant bacteria isolated from the clinical samples in Tamil Nadu, India. A total of 126 non-repetitive Gram-negative bacteria were taken for this study. The susceptibility to meropenem was determined by Minimum Inhibitory Concentration (MIC) by broth micro-dilution. The phenotypic resistance screening such as MHT (Modified Hodge test), EDTA disk synergy and CIM (carbapenem inactivation method) were performed. A multiplex PCR was used for the detection of carbapenemase-encoding genes. Among the 126 isolates studied, 82 (65.07%) meropenem-resistant isolates were identified by MIC. A total of 18 (21.9%) isolates were found to be positive for Metallo-{beta}-Lactamase production through EDTA synergy test. None of the isolates were carbapenemase producer by MHT and CIM. The isolates identified with resistance genes (8/82) were blaNDM-1 in two Klebsiella sp., two P. aeruginosa and one A. baumannii, blaVIM-1 in one P. aeruginosa and blaAIM-1 in one P. aeruginosa and one A. baumannii. The study showed the distribution and increase of carbapenem-resistant bacteria in the study region. Therefore, constant monitoring and effective elimination should be focused to reduce the spread of carbapenem-resistant isolates.

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Manohar, P., Joseph, A., Nair, K. B., AnuPriya, P., Mani, S. S., Varsha, V., Ramesh, N.. 2020-11-30. Detection of NDM-1, VIM-1 and AIM-type Metallo-beta-lactamase genes in Gram-negative bacteria isolated from clinical samples in Tamil Nadu. https://doi.org/10.1101/2020.11.29.403220

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