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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)

Published on: February 9, 2011

Predominant Dissemination of PVL-Negative CC89 MRSA with SCCmec Type II in Children with Impetigo in Japan

H Kikuta1, M Shibata, S Nakata

  • 1Pediatric Clinic, Touei Hospital, N-41, E-16, Higashi-ku, Sapporo 007-0841, Japan.

International Journal of Pediatrics
|December 22, 2011
PubMed

Insights

Community-associated Methicillin-resistant Staphylococcus aureus (CA-MRSA) is rising in Japanese children with impetigo. PVL-negative CC89-SCCmec type II strains are the most common CA-MRSA found in this population.

Area of Science:

  • Microbiology
  • Epidemiology
  • Infectious Diseases

Background:

  • Increasing prevalence of community-associated Methicillin-resistant Staphylococcus aureus (CA-MRSA) in pediatric impetigo cases in Japan.
  • Need to understand the molecular characteristics and antimicrobial resistance patterns of circulating S. aureus strains.

Purpose of the Study:

  • To investigate the antimicrobial susceptibilities, molecular epidemiology, and virulence factors of Staphylococcus aureus isolates from children with impetigo in Japan.
  • To identify the predominant CA-MRSA strains and their genetic makeup.

Main Methods:

  • Antimicrobial susceptibility testing of 136 S. aureus isolates.
  • Molecular epidemiological analysis including multilocus sequence typing (MLST) and staphylococcal cassette chromosome mec (SCCmec) typing.
  • Virulence gene analysis, specifically for lukS-PV-lukF-PV (Panton-Valentine leukocidin).

Main Results:

  • 10.3% of S. aureus isolates were MRSA (14/136).
  • The majority of MRSA strains (11/14) belonged to CC89 (ST89, ST91, ST2117) and carried SCCmec type II or IVa.
  • PVL genes were not detected in any isolates. Frequent gentamicin and clarithromycin resistance observed in both MRSA and MSSA.

Conclusions:

  • PVL-negative CC89-SCCmec type II strains are the predominant CA-MRSA strains in community-acquired pediatric impetigo in Japan.
  • The findings highlight the importance of molecular surveillance for understanding CA-MRSA epidemiology and guiding treatment strategies.

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