- Antibody mediated platelet destruction that leads to thrombocytopenia and prothrombotic state
- Typically 50% decline w/in 5-10d of treatment with heparin; or < 1 d if prior exposure to heparin
- Thrombocytopenia associated with arterial and/or venous thrombosis (e.g. skin necrosis, DVT, unexplained arterial thrombosis), adrenal hemorrhage, anaphylactic-type reaction after IV heparin infusion
- 4Ts score (link below) can help w/diagnosis
- DVT or arterial thrombotic events that occur linked to use of heparin and are otherwise unexplained