Epidemiology of bacterial resistance and detection of metallo-β-lactamase (blaNDM) and imipenemase (blaIMP) resistance genes at CERBA

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Résumé

Introduction: Antimicrobial resistance is a major public health concern. Producing new β-lactamases and carbapenemases is one form of resistance that preoccupies many scientists. The risk of the spread of carbapenemase-producing Enterobacteriaceae (EPCs) is a major public health issue, as these enzymes restrict therapeutic options and are often associated with other mechanisms, conferring multi-resistance on strains. Our study aimed to characterize the blaIMP and blaNDM resistance genes in Enterobacteriaceae isolates from urine cultures and genital swabs at CERBA from 2020 to 2023.
Methodology: Pathogens were isolated on agar media, then identified using the API 20 E gallery; Imipenem-resistant strains were subjected to the traditional Hodge test to verify carbapenemase production. Detection of the IMP and NDM resistance genes coding for carbapenemases was carried out by multiplex real-time PCR at CERBA.
Results: 1119 samples have been received for bacteriological analysis since January 2020. We noted 14.2% positivity to a clinically pathogenic strain. Bacterial species diversity was dominated by Escherichia coli in 54.71% of cases, followed by Klebsiella pneumoniae (15.72%). We observed a predominance of the NDM gene (97.9%) over IMP (2.1%). In some cases, we noted the coexistence of the IMP and NDM genes in Escherichia coli.
Conclusion: This study enabled us tocharacterize the IMP and NDM resistance genes in isolation (IMP/NDM) or coexisting together (IMP+NDM) in Enterobacteriaceae isolates at CERBA. This study also enabled us to determine the frequency of bacterial species inbacterial culture samples at CERBA.

Mots-clés

IMP, NDM, Enterobacteriaceae, β-lactamase, Carbapenemase