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The role of group C and group G streptococci in acute pharyngitis in children

T Zaoutis1, M Attia, R Gross

  • 1Department of Pediatrics, Alfred I. duPont Hospital for Children, Wilmington, Delaware, USA. zaoutis@email.chop.edu

Clinical Microbiology and Infection : the Official Publication of the European Society of Clinical Microbiology and Infectious Diseases
|January 7, 2004
PubMed

Insights

Large-colony-forming Group C and G streptococci (GCS/GGS) are uncommon causes of acute pharyngitis in children. This study found these bacteria rarely isolated from pediatric patients with sore throats, suggesting they are unusual pathogens.

Area of Science:

  • Microbiology
  • Pediatric Infectious Diseases
  • Bacteriology

Background:

  • Group C streptococci (GCS) and group G beta-haemolytic streptococci (GGS) are known causes of streptococcal pharyngitis epidemics in children.
  • The role of specific subtypes, like large-colony-forming strains, in endemic or sporadic pediatric pharyngitis remains unclear.

Purpose of the Study:

  • To investigate the prevalence and role of large-colony-forming GCS and GGS in acute, sporadic pharyngitis among children.
  • To determine if these specific bacterial strains are significant etiological agents in pediatric sore throat cases.

Main Methods:

  • A cross-sectional study was conducted over one year, enrolling 2085 children with pharyngitis and 194 controls.
  • Throat cultures were analyzed using standard methods, with beta-haemolytic isolates identified via Lancefield grouping and species identification.

Main Results:

  • A total of 65 (3%) large-colony-forming GCS and GGS strains were isolated from children with pharyngitis.
  • Only three (1.5%) such strains were found in the control group, yielding an odds ratio of 2.0 (95% CI 0.6-6.1).
  • The low isolation rate suggests these strains are infrequently associated with acute, sporadic pediatric pharyngitis.

Conclusions:

  • Large-colony-forming strains of Group C and G streptococci are infrequently isolated from children presenting with acute pharyngitis.
  • These organisms appear to be unusual pathogens in sporadic pediatric cases of sore throat, despite their role in epidemics.

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