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Study of T serotypes and Emm genotypes of Streptococcus pyogenes in children with pharyngitis and tonsillitis

Toshinari Okabe1, Sachiyo Takeda, Masatoshi Hida

  • 1Division of Reproductive Medicine, Perinatology and Gynecologic Oncology, Graduate School of Medicine, Nippon Medical School, Japan. tokabe@nms.ac.jp

Journal of Nippon Medical School = Nippon Ika Daigaku Zasshi
|July 2, 2011
PubMed

Insights

Group A Streptococcus (GAS) pharyngitis is linked to specific T serotypes and emm genotypes. This study identified T12 and T1 as common serotypes, and emm12 and emm1 as prevalent genotypes in throat infections.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Epidemiology

Background:

  • Streptococcus pyogenes, also known as group A Streptococcus (GAS), is a common bacterial pathogen.
  • GAS infections primarily affect the upper respiratory tract, leading to conditions like pharyngitis and tonsillitis.

Purpose of the Study:

  • To investigate the distribution of T serotypes and emm genotypes of GAS.
  • To analyze the antimicrobial susceptibility of GAS isolates.
  • To determine the correlation between T serotypes and emm genotypes in patients with pharyngitis and tonsillitis.

Main Methods:

  • Isolation and identification of GAS from throat swabs of patients.
  • Serotyping using T antigens.
  • Genotyping based on emm gene sequencing.
  • Antimicrobial susceptibility testing.

Main Results:

  • The most frequent T serotypes identified were T12 (40%) and T1 (28%).
  • The predominant emm genotypes were emm12 (44%) and emm1 (26%).
  • A strong correlation was observed between specific T serotypes and emm genotypes.

Conclusions:

  • T12 and emm12, along with T1 and emm1, are significant types of GAS causing pharyngitis and tonsillitis.
  • Understanding these prevalent types can aid in disease surveillance and management.

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