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

Highlights

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  122 (20.4%) of 599 carbapenem-resistant Enterobacterales (CRE) isolates carried bla _KPC genes .

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  Predominance of ST15 K. pneumoniae, whereas E. coli presented more diverse sequence types.

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  bla _KPC-bearing plasmids were diverse in size.

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  Three different models of genetic context of bla _KPC-2.

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  Hypothesis of circulation of resistant bacteria and transmission among hospitals.

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 IS Ecp1– bla _CTX-M and IS Kpn27– bla _KPC–ΔIS Kpn6 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.