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Implementation of a Permeable Membrane Insert-based Infection System to Study the Effects of Secreted Bacterial Toxins on Mammalian Host Cells
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Implementation of a Permeable Membrane Insert-based Infection System to Study the Effects of Secreted Bacterial Toxins on Mammalian Host Cells

Published on: August 19, 2016

[Molecular characterization of Streptococcus pyogenes from invasive disease and streptococcal toxic shock syndrome

F Traverso1, M Sparo, V Rubio

  • 1Hospital Ramón Santamarina, Tandil, Argentina. fernandotraverso@yahoo.com.ar

Revista Argentina De Microbiologia
|May 13, 2010
PubMed

Insights

Streptococcus pyogenes strains causing invasive disease and streptococcal toxic shock syndrome (STSS) show genetic diversity. emm1 and emm3 types were prevalent, and all isolates remained susceptible to common antibiotics, validating penicillin and clindamycin treatment.

Area of Science:

  • Microbiology
  • Genetics
  • Epidemiology

Context:

  • Streptococcus pyogenes is a common pathogen causing pharyngitis, scarlet fever, and impetigo.
  • Recent decades show a global increase in invasive Streptococcus pyogenes infections and streptococcal toxic shock syndrome (STSS).

Purpose:

  • To analyze the genetic diversity of Streptococcus pyogenes isolates.
  • To determine the distribution of virulence genes (spe, sme, ssa) in these isolates.
  • To evaluate the antibiotic susceptibility patterns of S. pyogenes causing invasive disease and STSS.

Summary:

  • Ten S. pyogenes isolates from blood cultures of hospitalized patients in Argentina (2000-2005) were studied.
  • Two main pulse field gel electrophoresis patterns were observed, with emm1-T1 and emm3-TNT types predominating.
  • Specific virulence gene profiles (spe, sme, ssa) were associated with different emm types.
  • All isolates were susceptible to penicillin, cefotaxime, erythromycin, clindamycin, chloramphenicol, tetracycline, and rifampicin.

Impact:

  • The study reveals genetic diversity among invasive S. pyogenes strains, with emm1 and emm3 types being most common.
  • Antibiotic susceptibility data confirm that penicillin and clindamycin remain effective for empirical treatment.
  • Findings contribute to understanding the epidemiology and guiding treatment strategies for invasive S. pyogenes infections.

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