Phenotypic and genotypic characterization of multidrug resistant and extended-spectrum β-lactamase-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-lactamase-producing Enterobacterales (ESBL-E) as critical pathogens for public health and requiring urgently new antibiotics. The aim of this study was to characterize phenotypically and genotypically ESBL-E 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 (AST) was done using the Kirby Bauer disc diffusion method and interpretated according to the CA-SFM recommendations. ESBL phenotypes were double screened using CHROMagar™ ESBL and double disk synergy test (DDST). The detection of resistance genes was performed using conventional and multiplex PCR methods. Results were analyzed with SPSS (version 21) and a p-value < 0.05 was considered statistically significant. Results A total of 152 Enterobacterales were isolated among 597 clinical samples including urine, blood, cervico-vaginal, urethral swabs and wound samples. 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%). Conclusion This study reveals the high burden of ESBL-E among clinical samples in the regional hospital in Dschang with the most common species being E. coli and K. pneumoniae. It confirmed the high occurrence of bla CTX−M and bla TEM among ESBL-E. The study suggests that implementing antimicrobial stewardship program and real-time surveillance of antimicrobial resistance are needed in the Western region of Cameroon. Moreover, the implementation of infection prevention and control measures (IPC) is essential to curb the dissemination of these bacteria from community to hospital settings. Implementation of national action plan to fight against antimicrobial resistance at the local levels is urgently needed.

Keywords

• Antibiotic resistance
• Enterobacterales
• ESBLs
• CTX-M
• Cameroon