Thrombocytopenia

Platelets come from megakariocytes and are produced in bone marrow and lung. Their development is stimulated by thrombopoeitin produced in liver and kidney. They are 2-3 um across. Platelet function follows the pattern: Adhesion -> Activation -> Aggregation. Platelet aggregation forms a platelet plug (primary hemostasis), which is stabilized by coagulation factors culminating in a fibrin mesh/net which stabilizes the platelet plug.

Spurious

• Clumping

Sequestration

• Hypersplenism

Destruction/Consumption

• HIGH IPF%, Prolonged PT / aPTT
• What happens to platelets after they help form a clot?
• DIC
• ITP
• TTP
• HUS
• HIT

Decreased Production

• LOW IPF%
• Parvo
• Aplastic Anemia
• Cancer
• Chemotherapy
• Liver disease?