title: Prevalence and Molecular Characteristics of Carbapenemase-Producing Enterobacteriaceae From Five Hospitals in Korea.
abstract: BACKGROUND
  The emergence of carbapenemase-producing Enterobacteriaceae (CPE) represents a major clinical problem because these bacteria are resistant to most antibiotics. CPE remain relatively uncommon in Korea. We report the prevalence, clinical characteristics, and molecular epidemiology of CPE isolates collected from five university hospitals in Korea.
  
  
  METHODS
  Between January and December 2015, 393 non-duplicated isolates that were nonsusceptible to ertapenem were analyzed. Production of carbapenemase, extended-spectrum β-lactamase, and AmpC β-lactamase was determined by genotypic tests. Antimicrobial susceptibility profiles were determined by using an Etest. Clonality of Klebsiella pneumoniae carbapenemase (KPC)-2-producing and oxacillinase (OXA)-232-producing Klebsiella pneumoniae isolates was determined by pulsed-field gel electrophoresis (PFGE).
  
  
  RESULTS
  Of the 393 isolates tested, 79 (20.1%) were CPE. Of these 79 isolates, 47 (59.5%) harbored the bla(OXA-232) gene while the remaining isolates carried genes bla(KPC-2) (n=27), bla(IMP-1) (n=4), and bla(NDM-1) (n=1). Among the 24 KPC-2 K. pneumoniae isolates from hospital B, 100% were resistant to carbapenems, 8% to colistin, and 0% to tigecycline. Among the 45 OXA-232 K. pneumoniae at hospital C, 95% were resistant to ertapenem, 68% to imipenem, 95% to meropenem, 10% to colistin, and 24% to tigecycline. PFGE analysis revealed a unique pattern for KPC-2 K. pneumoniae and identified 30 isolates belonging to the dominant pulsotypes (PT)1 and PT2 among 41 OXA-232 K. pneumoniae isolates.
  
  
  CONCLUSIONS
  CPE strains are present in Korea, with the majority of K. pneumoniae isolates producing OXA-232 and KPC-2. The prevalence and predominant genotypes of CPE show hospital-specific differences.
authors: Department of Laboratory Medicine and Research Institute for Antimicrobial Resistance, Yonsei University College of Medicine, Seoul, Korea.
authors: Seok Hoon
authors: SH
authors: Jeong
authors: Department of Laboratory Medicine, Hallym University College of Medicine, Chuncheon, Korea.
authors: Han Sung
authors: HS
authors: Kim
authors: Department of Laboratory Medicine, Hallym University College of Medicine, Chuncheon, Korea.
authors: Jae Seok
authors: JS
authors: Kim
authors: Department of Laboratory Medicine, Hallym University College of Medicine, Chuncheon, Korea.
authors: Dong Hoon
authors: DH
authors: Shin
authors: Department of Laboratory Medicine, Hallym University College of Medicine, Chuncheon, Korea.
authors: Hyun Soo
authors: HS
authors: Kim
authors: Department of Laboratory Medicine, Hallym University College of Medicine, Chuncheon, Korea.
authors: Min Jeong
authors: MJ
authors: Park
authors: Department of Laboratory Medicine, Hallym University College of Medicine, Chuncheon, Korea.
authors: Saeam
authors: S
authors: Shin
authors: Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
authors: Jun Sung
authors: JS
authors: Hong
authors: Department of Internal Medicine, Hallym University College of Medicine, Chuncheon, Korea.
authors: Seung Soon
authors: SS
authors: Lee
authors: Department of Laboratory Medicine, Hallym University College of Medicine, Chuncheon, Korea. swonkeun@hallym.or.kr.
authors: Wonkeun
authors: W
authors: Song
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D004755:Enterobacteriaceae / Q000187:drug effects / Q000201:enzymology* / Q000302:isolation & purification; D004756:Enterobacteriaceae Infections / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology*; D005260:Female; D005838:Genotype; D006761:Hospitals; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D015995:Prevalence; D056910:Republic of Korea / Q000453:epidemiology; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; C491478:beta-lactamase KPC-2; D001618:beta-Lactamases; C063912:carbapenemase; C108449:oxacillinase
keywords: Enterobacteriaceae; KPC-2; Klebsiella pneumoniae; Korea; OXA-232