Heparin induced thrombocytopenia HIT

• Facts:
  Typically occurs 5-10 days after heparin exposure
  
  1) Heparin induces platelet factor 4 (PF4) release from platelets
  
  2) Heparin and PF4 complexes form
  
  3) Antibodies bind to complexes, cause platelet activation and abnormal generation of intravascular thrombin
  
  4) Creates prothrombotic condition (both arterial and venous)
• Treatment:
  Discontinue ALL heparin products
  Argatroban or lepirudin (direct thrombin inhibitors)
• Associated With:
  Heparin
• Differential Diagnosis:
  Antiphospholipid antibody syndrome (increased PTT)