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Platelet Dysregulation in the Pathobiology of COVID-19

Rebecca A Mellema1, Jacob Crandell2, Aaron C Petrey1,2

  • 1Division of Microbiology and Immunology, Department of Pathology, University of Utah, Salt Lake City, Utah, United States.

Hamostaseologie
|December 8, 2021
PubMed

Insights

Severe COVID-19 involves thromboinflammation, with platelet alterations significantly impacting disease severity and outcomes. This review details these platelet changes and their role in COVID-19 pathobiology.

Area of Science:

  • Immunology
  • Hematology
  • Infectious Diseases

Background:

  • Coronavirus disease 2019 (COVID-19) presents with diverse clinical manifestations, often including hyperinflammation and thrombotic events in severe cases.
  • COVID-19 is recognized as a thromboinflammatory disease, with coagulation and platelet abnormalities linked to mortality.
  • Platelets, beyond hemostasis, play crucial roles in immune response regulation through various secreted and cell-surface molecules.

Purpose of the Study:

  • To review current knowledge on platelet alterations in COVID-19.
  • To elucidate the impact of these platelet changes on COVID-19 pathobiology.

Main Methods:

  • Literature review of studies investigating platelet function and characteristics in COVID-19 patients.
  • Synthesis of findings on platelet count, activation, aggregation, and their molecular mediators.

Main Results:

  • Significant alterations in platelet count and function are observed in COVID-19 patients.
  • Platelet activation and prothrombotic potential are heightened, contributing to microvascular and macrovascular thrombi.
  • Platelet-derived inflammatory mediators exacerbate hyperinflammation and multi-organ dysfunction.

Conclusions:

  • Platelet alterations are central to the thromboinflammatory state in severe COVID-19.
  • Understanding these platelet changes is critical for developing targeted therapies to improve clinical outcomes.

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