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Capsular Serotyping of Streptococcus pneumoniae by Latex Agglutination
09:11

Capsular Serotyping of Streptococcus pneumoniae by Latex Agglutination

Published on: September 25, 2014

[Antimicrobial sensitivity and characterization of Streptococcus pyogenes strains isoleated from a scarlatina

Alberto González Pedraza-Avilés1, Catalina Ortiz-Zaragoza, Ricardo Mota-Vázquez

  • 1Centro de Salud, Doctor José Castro-Villagrana, Servicios de Salud Pública del Distrito Federal, México, D.F., México.

Salud Publica De Mexico
|October 23, 2002
PubMed
Abstract

Insights

Group A Streptococcus strains showed sensitivity to betalactams and clindamycin, but resistance to erythromycin emerged. The M2 type was most common, often co-occurring with the SpeA gene.

Area of Science:

  • Microbiology
  • Molecular Epidemiology
  • Infectious Diseases

Context:

  • Scarlet fever outbreak in children (December 1999-January 2000).
  • Study conducted at Centro de Salud Dr. José Castro Villagrana.
  • Involved 137 children at Colegio Espíritu de América.

Purpose:

  • Evaluate in vitro antimicrobial activities against 47 Group A Streptococcus pyogenes (GAS) strains.
  • Determine the prevalence of streptococcal pyrogenic exotoxin A (SpeA) and M-protein serotypes.

Summary:

  • All GAS strains were susceptible to betalactams and clindamycin.
  • 12.7% of strains exhibited erythromycin resistance.
  • M2 serotype was most frequent (27 strains); 96% of SpeA-positive strains were M2 type.

Impact:

  • Highlights the need for ongoing molecular epidemiology of GAS.
  • Informs antimicrobial stewardship for GAS infections.
  • Provides data on macrolide and beta-lactam sensitivity crucial for treatment guidelines.

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