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Immunopathogenesis of streptococcal deep tissue infections

Linda Johansson1, Anna Norrby-Teglund

  • 1Karolinska Institutet, Center for Infectious Medicine, F59, Karolinska University Hospital Huddinge, S-141 86 Stockholm, Sweden. Linda.Johansson.2@ki.se

Current Topics in Microbiology and Immunology
|December 11, 2012
PubMed

Insights

Streptococcus pyogenes causes severe tissue infections like necrotizing fasciitis. This review explores bacterial virulence factors and host immune responses contributing to these complex, life-threatening S. pyogenes infections.

Area of Science:

  • Microbiology
  • Pathogenesis
  • Immunology

Background:

  • Streptococcus pyogenes is a significant human pathogen.
  • It causes diverse infections, from superficial to life-threatening deep tissue diseases like necrotizing fasciitis.
  • Infection pathogenesis is complex, involving multiple bacterial virulence factors.

Purpose of the Study:

  • To review epidemiologic, pathogenomic, and pathogenesis data on S. pyogenes tissue infections.
  • To elucidate host-pathogen interactions in these infections.
  • To highlight factors contributing to S. pyogenes-induced tissue pathology.

Main Methods:

  • Review of existing literature.
  • Analysis of epidemiologic data.
  • Examination of pathogenomic and pathogenesis studies.
  • Focus on in vivo findings from patient studies.

Main Results:

  • S. pyogenes employs tissue-specific types and immune evasion strategies, like intracellular persistence.
  • These lead to high bacterial loads and hyperinflammatory responses.
  • Host and bacterial factors at the infection site are crucial.

Conclusions:

  • Understanding S. pyogenes virulence factors and host responses is key to combating severe infections.
  • In vivo findings offer critical insights into disease mechanisms.
  • Further research into host-pathogen interactions can guide therapeutic strategies.

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