Epidemiological Study of an Outbreak of KPC-2 Producing Klebsiella pneumoniae in a Tertiary Hospital in Korea

Jun Sung Hong^1† Byeol Yi Park^1† Dokyun Kim^1* Kunhan Kim¹ Kyoung Hwa Lee² Nan Hyoung Cho³ Seok Hoon Jeong¹

¹ Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul,
² Division of Infectious Disease, Department of Internal Medicine, Yonsei University College of Medicine, Seoul,
³ Department of Infection Control, Gangnam Severance Hospital, Seoul,

Abstract

Background: The prevalence of carbapenemase-producing Enterobacteriaceae (CPE), especially the KPC-2-producing Klebisella pneumoniae, is rapidly increasing and becoming a menace to global public health. This study aims to present the molecular epidemiology of the KPC-2-producing K. pneumoniae isolates emerged in a tertiary hospital in South Korea and describe its clinical significance. Methods: This study included carbapenem-resistant K. pneumoniae isolates collected from a tertiary hospital from April to December in 2018. Antimicrobial susceptibility of K. pneumoniae isolates was tested using disk diffusion method. PCR and DNA sequence analyses were performed to identify the resistance genotype. In addition, the molecular epidemiology was investigated using pulsed-field gel electrophoresis (PFGE) and multilocus sequencing typing (MLST). Results: Total 100 KPC-2-producing K. pneumoniae isolates were collected, which were mainly classified into two pulsotypes according to the XbaI restriction digestion pattern by PGFE analysis (pulsotype A, n = 31; pulsotype B, n = 63). The isolates exhibiting pulsotype A belonged to ST395 and the remaining isolates exhibiting pulsotype B were attributed to ST307 by MLST analysis. Conclusion: This study investigated clinical information and molecular bacterial profiles for KPC-2-producing K. pneumoniae isolates. These findings indicate that the proper infection control activities are needed to prevent the spread of multidrug-resistant organisms such as CPE, which could cause high mortality in clinical field.

Keywords

Carbapenemase KPC Klebsiella pneumoniae PFGE

Figures & Tables

Figure 1. Monthly isolation of KPC-2 producing K. pneumoniae isolates stratified by PFGE banding patterns. Bar graphs indicate the numbers of KPC-2 producing K. pneumoniae isolates collected in each nine month in 2018 and arrows indicate the activity performed for eradicating a KPC-type carbapenemase producing K. pneumoniae isolates outbreak. Yellow bar, pulsotype A; Blue bar, pulsotype B; Gray bar, other pulsotypes.

Figures & Tables

Table 1. Oligonucleotide sequence of the primers used in this study

Target gene	Primer name	Primer sequence (5' to 3')	Amplicon size (bp)
blaCTX-M-1	CTX-M-1_-48–25F	GACTATTCATGTTGTTGTTAWTTC	973
	CTX-M-1_+28-+49R	TAAGGCGATAAACAAAAACGGA
blaCTX-M-9	CTX-M-9_-42—21F	GAATACTGATGTAACACGGATT	962
	CTX-M-9-1_+23-+44R	ATATAAATAGAAAGTGGGGCAC
	CTX-M-9-2_+27-+46R	CTGATCCTTCAACTCAGCAA
blaCMY	MOXM F	GCTGCTCAAGGAGCACAGGAT	520
	MOXM R	CACATTGACATAGGTGTGGTGC
blaCMY-2	CITM F	TGGCCAGAACTGACAGGCAAA	462
	CITM R	TTTCTCCTGAACGTGGCTGGC
blaDHA	DHAM F	AACTTTCACAGGTGTGCTGGGT	405
	DHAM R	CCGTACGCATACTGGCTTTGC
blaACC	ACCM F	AACAGCCTCAGCAGCCGGTTA	346
	ACCM R	TTCGCCGCAATCATCCCTAGC
blaACT	EBCM F	TCGGTAAAGCCGATGTTGCGG	302
	EBCM R	CTTCCACTGCGGCTGCCAGTT
blaFOX	FOXM F	AACATGGGGTATCAGGGAGATG	190
	FOXM R	CAAAGCGCGTAACCGGATTGG
blaKPC	KPC F	ATGTCACTGTATCGCCGTCT	882
	KPC R	TTTTCAGAGCCTTACTGCCC