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THE OCCURRENCE OF ROUGH PNEUMOCOCCI IN VIVO

J R Paul1

  • 1Ayer Clinical Laboratory, Pennsylvania Hospital, Philadelphia.

The Journal of Experimental Medicine
|October 30, 2009
PubMed

Insights

Researchers isolated rough pneumococci (R pneumococci) from human respiratory infections. Two strains exhibited characteristic autolysis and serological reactions, suggesting R pneumococci can occur in human sputum.

Area of Science:

  • Microbiology
  • Bacteriology
  • Immunology

Background:

  • Respiratory infections are common, often caused by Streptococcus pneumoniae.
  • Pneumococci exist in various forms, including rough (R) and smooth (S) variants.
  • Understanding pneumococcal variants is crucial for infection control and host response.

Purpose of the Study:

  • To investigate the presence and characteristics of rough pneumococci in human sputum.
  • To determine if R pneumococci can be isolated from patients with respiratory infections.

Main Methods:

  • Surveyed sputum cultures from individuals with respiratory infections.
  • Isolated and studied rough, methemoglobin-producing colonies.
  • Performed bile solubility tests and autolysis assays.
  • Conducted serological analyses to identify R pneumococci.

Main Results:

  • Isolated twelve bile-soluble strains suspected to be R pneumococci from approximately forty rough colonies.
  • Two of the twelve isolated strains demonstrated autolysis in saline solution.
  • These two strains also showed serological reactions characteristic of R pneumococci.

Conclusions:

  • R pneumococci can occasionally be found in human sputum.
  • The presence of R pneumococci in sputum suggests a potential role in pneumococcus epidemiology.
  • Further research is needed to understand the implications for host response and infection dynamics.

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