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Two unusual cases of severe soft tissue infection caused by Streptococcus dysgalactiae subsp. equisimilis

Bård Reiakvam Kittang1, Nina Langeland, Steinar Skrede

  • 1Institute of Medicine, University of Bergen, 5021 Bergen, Norway. brki@helse-bergen.no

Journal of Clinical Microbiology
|February 12, 2010
PubMed

Insights

Invasive infections from Streptococcus dysgalactiae subsp. equisimilis can be severe. Even mutated strains causing necrotizing fasciitis and septic shock highlight the need for vigilance.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Clinical Medicine

Background:

  • Streptococcus dysgalactiae subsp. equisimilis is a known pathogen.
  • The emm gene encodes the M protein, crucial for virulence in streptococci.

Observation:

  • Two cases of invasive Streptococcus dysgalactiae subsp. equisimilis infection are detailed.
  • One patient developed rapidly progressing necrotizing fasciitis.
  • Another patient experienced severe cellulitis and septic shock.

Findings:

  • The bacterium in the second case had a mutated emm gene, leading to a truncated M protein.
  • Despite the mutation, severe invasive disease occurred.

Implications:

  • This highlights the potential for Streptococcus dysgalactiae subsp. equisimilis to cause severe invasive infections.
  • The findings suggest that M protein truncation does not always attenuate virulence.
  • Further research into Streptococcus dysgalactiae subsp. equisimilis virulence factors is warranted.

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