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Updated: Jun 19, 2026
09:34
Pneumococcus Infection of Primary Human Endothelial Cells in Constant Flow
Published on: October 31, 2019
THE BLOOD PLATELETS IN PNEUMOCOCCUS INFECTIONS.
1Hospital of The Rockefeller Institute for Medical Research.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Pneumonia infection causes a drop in blood platelet counts, with numbers returning to normal weeks after fever subsides. Subsequent fevers can cause platelet counts to drop again.
Area of Science:
- Hematology
- Infectious Diseases
- Pulmonary Medicine
Background:
- Pneumonia is a significant respiratory infection.
- Understanding the hematological changes during pneumonia is crucial for patient management.
Purpose of the Study:
- To investigate the behavior of blood platelets during pneumonia in humans and experimentally infected rabbits.
- To correlate platelet count variations with different stages of pneumonia and its sequelae.
Main Methods:
- Observational study of human pneumonia patients.
- Experimental infection of rabbits with pneumococci.
- Monitoring of blood platelet counts throughout the disease course, including febrile, crisis, postfebrile, and sequelae periods.
Main Results:
- A decrease in platelet count (thrombopenia) was observed during the established infection and febrile period.
- Platelet counts increased significantly above normal after the crisis or lysis, returning to baseline after approximately two weeks.
- Recurrent fevers associated with pneumonia sequelae led to renewed platelet count diminution.
- Platelets appeared smaller and more granular during the thrombopenic phase.
- Antipneumococcus serum administration did not typically alter platelet counts.
Conclusions:
- Blood platelet dynamics are significantly altered during pneumonia, reflecting disease activity and resolution.
- Platelet count serves as a potential indicator of pneumonia progression and recovery.
- Further research into the role of platelets in pneumonia pathogenesis and immune response is warranted.
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