Emergence of Panton-Valentine leucocidin-positive ST8-methicillin-resistant Staphylococcus aureus (USA300 clone) in Korea causing healthcare-associated and hospital-acquired bacteraemia

Eur J Clin Microbiol Infect Dis. 2016 Aug;35(8):1323-9. doi: 10.1007/s10096-016-2668-y. Epub 2016 May 21.

Abstract

Panton-Valentine leucocidin (PVL)-positive sequence type (ST)8-MRSA-SCCmec IVa (USA300) is the epidemic strain of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in North America. USA300 is extremely rare in South Korea, and PVL-negative ST72 SCCmec type IVc is the predominant CA-MRSA clone. In a multicentre, prospective cohort study of S. aureus bacteraemia, we identified PVL-positive ST8-MRSA isolates by performing multilocus sequence typing and PCR for PVL. We analyzed the clinical characteristics of patients with PVL-positive ST8-MRSA bacteraemia, and performed SCCmec, spa, and agr typing, PCR for arginine catabolic mobile element (ACME), virulence gene profiling, and pulsed-field gel electrophoresis (PFGE). Among a total of 818 MRSA isolates, we identified ten isolates of PVL-positive ST8-MRSA (USA300) (3 from Hospital D, 4 from Hospital G, and 3 from Hospital A), all of which involved exclusively healthcare-associated (5 isolates) and hospital-acquired bacteraemia (5 isolates). This strain accounted for 8~10 % of the hospital-acquired MRSA bacteraemia in Hospitals D and G. Bacteraemia of unknown origin was the most common type of infection followed by pneumonia. All the isolates were SCCmec type IVa, spa type t008, and agr group I. Eight of the isolates harboured ACME. In a PFGE analysis, four isolates were identical to the USA300 control strain, five differed by a single band, and the remaining one differed by two bands. All the isolates were pulsed-field type USA300. This is the first report of healthcare-associated and hospital-acquired bacteraemia caused by USA300 in South Korea. USA300 seems to be an emerging hospital clone in this country.

Publication types

  • Multicenter Study

MeSH terms

  • Bacteremia* / epidemiology
  • Bacteremia* / microbiology
  • Bacterial Toxins*
  • Communicable Diseases, Emerging / epidemiology
  • Communicable Diseases, Emerging / microbiology
  • Cross Infection* / epidemiology
  • Cross Infection* / microbiology
  • Disease Outbreaks / statistics & numerical data*
  • Exotoxins*
  • Humans
  • Incidence
  • Leukocidins*
  • Methicillin-Resistant Staphylococcus aureus* / genetics
  • Methicillin-Resistant Staphylococcus aureus* / isolation & purification
  • Methicillin-Resistant Staphylococcus aureus* / pathogenicity
  • Prevalence
  • Prospective Studies
  • Republic of Korea / epidemiology
  • Staphylococcal Infections* / epidemiology
  • Staphylococcal Infections* / microbiology

Substances

  • Bacterial Toxins
  • Exotoxins
  • Leukocidins
  • Panton-Valentine leukocidin