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Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus
09:03

Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus

Published on: September 5, 2013

[Molecular epidemiology of methicillin-resistant Staphylococcus aureus isolates with toxic shock syndrome toxin and

Jae Seok Kim1, Han Sung Kim, Wonkeun Song

  • 1Department of Laboratory Medicine, Hallym University College of Medicine, Korea.

The Korean Journal of Laboratory Medicine
|December 21, 2007
PubMed
Abstract

Insights

Methicillin-resistant Staphylococcus aureus (MRSA) strains in Korea carrying toxic shock syndrome toxin (tst) and staphylococcal enterotoxin C (sec) genes are genetically related. Pulsed-field gel electrophoresis (PFGE) suggests clonal spread of these specific MRSA strains across hospitals.

Area of Science:

  • Microbiology
  • Genetics
  • Epidemiology

Context:

  • Methicillin-resistant Staphylococcus aureus (MRSA) isolates in Korea frequently harbor both the toxic shock syndrome toxin gene (tst) and the staphylococcal enterotoxin C gene (sec).
  • The majority of these MRSA isolates belong to staphylococcal cassette chromosome mec (SCCmec) type II, indicating a potential shared genetic origin.
  • Investigating the genetic relatedness of these co-harboring strains is crucial for understanding their epidemiology and spread.

Purpose:

  • To determine the genetic relatedness of MRSA isolates in Korea that possess both tst and sec genes.
  • To analyze the genetic profiles of SCCmec type II MRSA strains carrying tst and sec using pulsed-field gel electrophoresis (PFGE).

Summary:

  • Fifty-nine MRSA isolates of SCCmec type II, positive for tst and sec, were analyzed using PFGE.
  • The isolates clustered into 11 distinct PFGE types, with a major group comprising 26 strains from multiple healthcare facilities.
  • Over half of the isolates (55 out of 59) belonged to seven PFGE types, indicating significant genetic similarity.

Impact:

  • The findings suggest a clonal spread of MRSA strains carrying tst and sec within Korean hospitals.
  • Identical PFGE patterns observed across different healthcare facilities highlight the interconnectedness of MRSA transmission.
  • This study provides insights into the molecular epidemiology of specific MRSA strains in healthcare settings.

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