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Invasive infection caused by Streptococcus dysgalactiae subsp. equisimilis: characteristics of strains and clinical

Takashi Takahashi1, Kimiko Ubukata, Haruo Watanabe

  • 1Laboratory of Infectious Diseases, Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan. taka2si@lisci.kitasato-u.ac.jp

Journal of Infection and Chemotherapy : Official Journal of the Japan Society of Chemotherapy
|July 8, 2010
PubMed

Insights

Streptococcus dysgalactiae subsp. equisimilis (SDSE) is an emerging pathogen causing invasive infections globally, particularly in elderly patients. Understanding its virulence factors and epidemiology is crucial for developing effective treatments and vaccines.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Epidemiology

Background:

  • Streptococcus pyogenes and Streptococcus agalactiae were historically the primary beta-hemolytic streptococcal pathogens in humans.
  • Streptococcus dysgalactiae subsp. equisimilis (SDSE), identified in 1996, is increasingly recognized as a significant human pathogen.
  • SDSE shares virulence factors with Streptococcus pyogenes and can colonize various human body sites.

Purpose of the Study:

  • To review the phenotypic characteristics and virulence factors of SDSE.
  • To highlight the emergence of invasive SDSE infections worldwide, with a focus on elderly populations.
  • To discuss the molecular epidemiology of SDSE and explore future vaccination strategies.

Main Methods:

  • Phenotypic characterization of SDSE strains.
  • Analysis of virulence factors, including M protein, streptolysin O, and streptokinase.
  • Molecular epidemiology using emm gene sequencing.
  • Review of clinical case data and surveillance reports.

Main Results:

  • SDSE possesses multiple virulence factors similar to Streptococcus pyogenes.
  • Invasive SDSE infections, such as cellulitis, urosepsis, and pneumonia, are increasingly diagnosed globally.
  • Molecular epidemiology reveals variations in emm type distribution across different countries.
  • Elderly patients are disproportionately affected by invasive SDSE infections, especially in Japanese emergency departments.

Conclusions:

  • SDSE is an emerging pathogen of global concern, necessitating further research into its pathogenesis and transmission.
  • Understanding the molecular epidemiology of SDSE is vital for effective disease surveillance and control.
  • Future research should focus on developing targeted vaccines and therapies against SDSE infections.

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