Phenotypic and genotypic characterization of multidrug resistant (MDR) and extended-spectrum β-lactamase (ESBL)-producing Enterobacterales isolated from clinical samples in the Western region in Cameroon

Abstract

Abstract Background: The 2017 World Health Organization (WHO) report has listed extended spectrum β-lactamases producing Enterobacterales (ESBL-PE) as critical pathogens for public health and requiring urgently new antibiotics. The aim of this study was to characterize phenotypically and genotypically ESBL-PE isolated among clinical samples in Dschang, Cameroon. Methods: A cross-sectional study was conducted during a four-month periods from February to May 2022 in the two biggest hospitals of Dschang. Clinical samples were collected and cultured on Eosin Methylene Blue agar. Suspected growing colonies were biochemically identified using the Enterosystem Kit 18R. Antimicrobial susceptibility testing was done using the Kirby Bauer disc diffusion method and interpretated according to the CA-SFM recommendations. ESBL phenotypes were double screened using CHROMagarTM ESBL and double disk synergy test (DDST). The detection of resistance genes was performed using conventional and multiplex PCR methods. Results were analysed with SPSS (version 21) and a p-value <0.05 was considered statistically significant. Results: A total of 597 clinical samples including urine, blood, cervico-vaginal and urethral swabs and wound samples were analyzed and 152 Enterobacterales where isolated among the 124 positives patients to Enterobacterales. The overall prevalence of ESBL-Enterobacterales was 29.61% (45/152). The most represented ESBL species were Escherichia coli (n=23; 51.11%), Klebsiella pneumoniae (n=8; 17.78%) and Citrobacter freundii (n=6; 13.33%). Antimicrobial resistance profile of ESBL-E. coli shows 56.52% and 86.96% resistance for imipenem and ceftazidime respectively. The most common genes detected among ESBL-Enterobacterales were blaCTX-M (n=38; 84.44%) and blaTEM (n= 33; 73.33%) respectively. Conclusion: ESBL-PE is an important public health concern in the Western region of Cameroon urging the implementation of real-time molecular epidemiological surveillance system in both hospitals and community settings combined with strict compliance of the National Action Plan on antimicrobial resistance.