22. Blood coagulation: cellular components (platelets, endothelial cells) and their laboratory analysis.

• Vasculopathies – endothelial dysfunction
  • Ehlers-Danlos
  • Marfan
  • Bleeding time prolonged
• Thrombocytopathies – plt dysfunction
  • Platelet count and volume
    • Measured by impedance or light scatter with flow cytometry
  • Thrombocytopaenia
    • Heparin induced (HIT)
      • Immunoassay tests for antibodies (type 2)
  • Thrombocytosis
    • Inflammation
    • Iron deficiency
  • Thrombocythaemia
    • Myeloproliferative disease
  • Thrombocyte dysfunction
    • von Willebrand disease
    • Bernard-Soulier syndrome
    • Glanzmann thrombasthenia
  • Platelet aggregometry
    • Photometric measurement
    • Pro-aggregation factors are added (ADP, arachidonic acid, ristocetin)
      • Sample clears up -> transmittance increases
      • Disease examined depends on the factor added
        • Arachidonic acid – monitor aspirin
        • ADP – monitor clopidogrel, etc
        • Ristocetin – monitor von Willebrand disease, Bernard-Soulier