Info
🌱 來自: Huppert’s Notes
Thrombotic Disorders🚧 施工中
Thrombotic Disorders
Inherited hypercoagulable states
• Factor V Leiden: Autosomal dominant disorder, but heterozygotes have an increased risk of thrombosis (avoid OCPs). Mutated form of Factor V lacks cleavage site for deactivation by Protein C.
• Prothrombin G20201A: Point mutation in the 3’ untranslated region of prothrombin so ↑prothrombin → ↑thrombin → ↑thrombus risk
• Protein C/S deficiency: Autosomal dominant disorder. Normally, protein C and S inactivate factor V, VIII. Can cause increased risk of warfarin skin necrosis.
• Anti-thrombin (AT) deficiency: Autosomal dominant disorder. AT normally inactivates thrombin and factors II, VII, IX–XII.
• Antiphospholipid syndrome (APLS): Associated with SLE. Autoantibody against protein bound to phospholipids.
- Clinical features: Venous and arterial clots, placental thrombosis (pregnancy loss), stroke, ↑PTT (antibodies interfere with the assay)
- Diagnosis: Sapporo criteria – at least 1 lab abnormality + 1 clinical abnormality
• Laboratory criteria (must confirm on two or more occasions, >12 weeks apart):
- Anticardiolipin antibodies (IgG or IgM)
- Anti-ß2**-**glycoprotein I antibodies (IgG or IgM)
- Lupus anticoagulant
• Clinical features:
- Vascular thrombosis
- Pregnancy morbidity
- Treatment: Lifelong anticoagulation with warfarin (DOACs inferior in APLS), heparin during pregnancy
Secondary hypercoagulable states
• Differential diagnosis: Malignancy, myeloproliferative disorders, oral contraceptive pills (OCPs), immobilization, trauma, nephrotic syndrome, HIT, DIC