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Whole blood platelet aggregation and coagulation factors in patients with systemic sclerosis

M J Goodfield1, M A Orchard, N R Rowell

  • 1Department of Dermatology, General Infirmary, Leeds.

British Journal of Haematology
|August 1, 1993
PubMed

Insights

Systemic sclerosis primarily enhances platelet sensitivity to collagen, indicating a primary platelet change. This heightened sensitivity, combined with elevated adhesive proteins, may contribute to disease progression.

Area of Science:

  • Hematology
  • Rheumatology
  • Immunology

Background:

  • Platelet function alterations are observed in systemic sclerosis (SSc), but their primary or secondary nature remains unclear.
  • Understanding these changes is crucial for elucidating SSc pathogenesis and potential therapeutic targets.

Purpose of the Study:

  • To investigate platelet aggregation sensitivity to various agonists in patients with systemic sclerosis (SSc).
  • To compare platelet function and plasma levels of specific proteins in SSc patients versus controls with Raynaud's disease and systemic lupus erythematosus (SLE).

Main Methods:

  • Whole blood platelet aggregation assays were performed using collagen, ADP, and adrenaline.
  • Plasma levels of fibrinogen and von Willebrand factor antigen (vWF:Ag) were measured.
  • Comparisons were made between SSc patients, healthy controls, Raynaud's disease patients, and SLE patients.

Main Results:

  • Systemic sclerosis patients exhibited significantly enhanced platelet sensitivity to collagen (P > 0.001).
  • No significant enhancement in platelet response to ADP or adrenaline was observed in SSc.
  • Elevated plasma levels of vWF:Ag and fibrinogen were found in SSc patients.

Conclusions:

  • The enhanced collagen-induced platelet sensitivity in SSc appears to be a primary platelet defect.
  • Elevated vWF:Ag and fibrinogen levels in SSc may synergize with primary platelet changes.
  • These findings suggest a multifactorial contribution to thrombotic risk in systemic sclerosis.

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