Tóm tắt

Introduction: Plasmid-mediated class C β-lactamase (pAmpC) is a member of broad-spectrum β-lactamase that spreads worldwide. However, its prevalence was under-evaluated.

Objective: To characterize the prevalence and distribution of pAmpC types in 294 cefoxitin (FOX) and third-generation cephalosporin (3GC) resistant Enterobacteriaceae collected in several regions of Thailand and Vietnam in 2018 and 2020.

Methods: Multiplex Polymerase Chain Reaction (PCR) for pAmpC identification was utilized to investigate prevalence and diversification of pAmpC among 294 cefoxitin and third-generation cephalosporin resistant Enterobacteriaceae isolated from Thailand (n= 197) and Vietnam (n= 97).

Results: The prevalence of pAmpC was 37.1% found in second and third-generation cephalosporin resistant Enterobacteriaceae. CMY-2 like was prominent in Thailand and Vietnam; however, prevalence of CMY-2 was varied in each hospital. DHA contributed 25.7%, ACT/MIR rate was dominant in Chiang Rai hospital, reached 100% in Thanh Hoa Pediatrics hospital. Worrisome, 3.7% - isolates carried two types of pAmpC. The incidence of pAmpC in Vietnam was significantly higher than those in Thailand.

Conclusions: These findings provide evidence-based of highly spreading and diversified distribution of transferable AmpC among Enterobacteriaceae in two Asia-Pacific countries.