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Clinical and microbiologic characteristics of group A streptococcal necrotizing fasciitis in children

Philippe Minodier1, Philippe Bidet, Fabien Rallu

  • 1Department of Pediatrics, CHU Sainte-Justine, Montréal, Canada.

The Pediatric Infectious Disease Journal
|June 9, 2009
PubMed

Insights

Group A Streptococcus necrotizing fasciitis is increasing in Montréal. In children, varicella and the speC gene in bacteria are linked to this severe infection.

Area of Science:

  • Pediatric Infectious Diseases
  • Bacteriology
  • Epidemiology

Background:

  • Group A Streptococcus (GAS) infections can lead to severe invasive diseases.
  • Necrotizing fasciitis (NF) is a rapidly progressing soft tissue infection with high morbidity and mortality.
  • An increased incidence of GAS NF has been noted in Montréal, Canada.

Purpose of the Study:

  • To investigate clinical features and bacterial virulence factors associated with invasive GAS infections in children.
  • To identify risk factors for the development of GAS necrotizing fasciitis in pediatric patients.

Main Methods:

  • Retrospective analysis of clinical data from children hospitalized with invasive GAS infections.
  • Molecular analysis of GAS strains to identify virulence factor genes, including speC.
  • Comparison of features between patients with and without necrotizing fasciitis.

Main Results:

  • Varicella (chickenpox) was identified as a significant clinical feature associated with GAS NF.
  • The presence of the streptococcal pyrogenic exotoxin C (speC) gene in GAS isolates was strongly associated with necrotizing fasciitis.
  • Specific virulence factors may predispose to severe GAS infections in children.

Conclusions:

  • Varicella and the speC gene are key factors associated with necrotizing fasciitis in children with invasive Group A Streptococcus infections.
  • Understanding these associations can aid in early recognition and management of severe GAS disease.
  • Further research into GAS virulence and host factors is warranted.

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