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Published on: January 17, 2014

Characteristics of Streptococcus pyogenes strains isolated from Chinese children with scarlet fever

Yunmei Liang1, Xuzhuang Shen, Guoying Huang

  • 1Beijing Children's Hospital, Affiliated to the Capital Medical University, Beijing, China.

Acta Paediatrica (Oslo, Norway : 1992)
|August 12, 2008
PubMed
Abstract

Insights

Streptococcus pyogenes isolates from Chinese children show high resistance to macrolides and tetracycline, primarily carrying the ermB gene and cMLSB phenotype. Common emm types, emm1.0 and emm12.0, exhibit varying speA and speC frequencies.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Molecular Epidemiology

Background:

  • Streptococcus pyogenes is a significant pathogen causing scarlet fever in children.
  • Understanding antibiotic resistance patterns and virulence factors is crucial for effective treatment and control.

Purpose of the Study:

  • To characterize Streptococcus pyogenes isolates from Chinese children with scarlet fever.
  • To analyze antibiotic resistance, macrolide resistance genes, superantigens, and emm types.

Main Methods:

  • Minimal inhibitory concentration testing against nine antibiotics.
  • Polymerase chain reaction (PCR) for macrolide resistance genes (mefA, ermB, ermA), superantigens (speA, speC), and emm genes.
  • Analysis of 145 S. pyogenes isolates from Beijing and Shanghai in 2007.

Main Results:

  • High resistance rates observed: 97.9% to macrolides and 96.6% to tetracycline.
  • All isolates were sensitive to chloramphenicol, penicillin, cefradine, and ofloxacin.
  • Predominant ermB gene (90.3%) and cMLSB phenotype (94.5%) were identified. Common emm types were emm1.0 and emm12.0, with varying speA and speC carriage.

Conclusions:

  • S. pyogenes isolates in China exhibit substantial resistance to macrolides and tetracycline.
  • The ermB gene and cMLSB phenotype are prevalent in these isolates.
  • emm1.0 and emm12.0 are common emm types, differing in superantigen (speA, speC) prevalence.

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