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Characterization of Inflammatory Responses During Intranasal Colonization with Streptococcus pneumoniae
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Intracellular reservoir of Streptococcus pyogenes in vivo: a possible explanation for recurrent pharyngotonsillitis

A Osterlund1, R Popa, T Nikkilä

  • 1Department of Clinical Microbiology, University Hospital, Uppsala, Sweden.

The Laryngoscope
|May 1, 1997
PubMed

Insights

Recurrent Streptococcus pyogenes infections may stem from bacteria hiding inside respiratory cells. These intracellular bacteria can re-emerge after antibiotic treatment, causing reinfection.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Cell Biology

Background:

  • Recurrent pharyngotonsillitis caused by Streptococcus pyogenes (S. pyogenes) is a common clinical challenge.
  • Previous research indicated S. pyogenes can survive intracellularly within respiratory epithelial cells.
  • Extracellular antibiotic removal led to the re-emergence of viable intracellular S. pyogenes.

Purpose of the Study:

  • To investigate the in vivo presence of intracellular S. pyogenes in patients with tonsillitis and asymptomatic carriers.
  • To determine if intracellular S. pyogenes contribute to recurrent infections.

Main Methods:

  • Collection of respiratory epithelial cells from patients with tonsillitis.
  • Collection of tonsils from asymptomatic S. pyogenes carriers.
  • Utilized electron microscopy and immunohistochemistry to detect intracellular S. pyogenes.

Main Results:

  • Intracellular S. pyogenes were identified in 93% of patients with tonsillitis (pharyngeal epithelial cells).
  • In asymptomatic carriers, intracellular S. pyogenes were found in 73% of macrophage-like cells and 36% of epithelial cells.
  • These findings confirm the in vivo presence of intracellular S. pyogenes.

Conclusions:

  • Intracellular S. pyogenes in pharyngeal epithelial cells represent a significant reservoir.
  • This intracellular reservoir strongly supports the hypothesis of bacterial re-emergence causing recurrent tonsillitis.
  • Targeting intracellular S. pyogenes may be crucial for effective treatment of recurrent pharyngotonsillitis.

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