Expansion of KPC-producing Enterobacterales in four large hospitals in Hanoi, Vietnam

Abstract

Objectives: The incidence of carbapenem resistance among nosocomial Gram-negative bacteria in Vietnam is high and increasing, including among Enterobacterales. In this study, we assessed the presence of one of the main carbapenemase genes, bla_KPC, among carbapenem-resistant Enterobacterales (CRE) from four large hospitals in Hanoi, Vietnam, between 2010 and 2015, and described their key molecular characteristics.

Methods: KPC-producing Enterobacterales were detected using conventional PCR and were further analysed using S1 nuclease pulsed-field gel electrophoresis (S1-PFGE), Southern blotting and whole-genome sequencing (WGS) for sequence typing and genetic characterisation.

Results: bla_KPC genes were detected in 122 (20.4%) of 599 CRE isolates. bla_KPC-carrying plasmids were diverse in size. Klebsiella pneumoniae harbouring bla_KPC genes belonged to ST15 and ST11, whereas KPC-producing Escherichia coli showed more diverse sequence types including ST3580, ST448, ST709 and ST405. Genotypic relationships supported the hypothesis of circulation of a population of 'resident' resistant bacteria in one hospital through the years and of transmission among these hospitals via patient transfer. WGS results revealed co-carriage of several other antimicrobial resistance genes and three different genetic contexts of bla_KPC-2. Among these, the combination of ISEcp1-bla_CTX-M and ISKpn27-bla_KPC-ΔISKpn6 on the same plasmid is reported for the first time.

Conclusion: We describe the dissemination of bla_KPC-expressing Enterobacterales in four large hospitals in Hanoi, Vietnam, since 2010, which may have started earlier, along with their resistance patterns, sequence types, genotypic relationship, plasmid sizes and genetic context, thereby contributing to the overall picture of the antimicrobial resistance situation in Enterobacterales in Vietnam.

Keywords: Carbapenem resistance; Enterobacterales; KPC; Vietnam.