II. History: Findings suggestive of Hypercoagulable State
- Thrombosis at a young age (age under 50 years)
- Family History of thrombosis before age 50 years old
- Recurrent Thrombosis
- Thrombosis in an unusual site (hepatic, mesenteric, splenic or cerebral vein)
- Recurrent Pregnancy Loss (frequent Miscarriage)
- Arterial AND Venous thrombosis
- Idiopathic venous thrombembolism or unprovoked VTE (No known predisposing factors)
III. Causes: Primary Hypercoagulable States (Hereditary)
- Common Causes
- Factor V Leiden Defect
- Prothrombin 20210
- Homocystinuria or Hyperhomocysteinemia
- Uncommon Causes
IV. Causes: Secondary or Acquired Hypercoagulable States
- Antiphospholipid Antibody Syndrome (most common)
- Pregnancy
- Surgery
- Trauma
- Infection or Sepsis
- Malignancy
- Cancer in idiopathic Hypercoagulability with unprovoked VTE: 3.9% (as high as 20% in some studies)
- Basic evaluation for occult malignancy
- Medications
- Myeloproliferative disorder
- Hyperlipidemia
- Homocystinuria
- Lupus Inhibitor
- Nephrotic Syndrome
V. Labs: Indications for testing based on level of suspicion
-
General
- Hold blood for tests below before Anticoagulation
- Avoid testing during acute event (inflammation and Anticoagulation may alter results)
- Delay test timing until
- Two weeks after stopping Warfarin
- Three days after stopping DOACs
- Continuous therapy for at least 2 to 3 months (consult hematology for testing on Anticoagulation)
- Risk of Thrombophilia determines level of testing
- Unlikely to be thrombophilic
- Criteria
- First episode of Venous Thromboembolism and
- Known Thromboembolism Risk Factors and
- No Family History of Thromboembolism
- No first degree relative under age 50 years
- Testing
- No testing indicated
- Criteria
- Weakly thrombophilic
- Criteria
- Age over 50 years and
- First thromboembolic episode and
- No known Thromboembolism Risk Factors
- No Family History of Thromboembolism
- No first degree relative under age 50 years
- Testing
- Evaluation of common causes (see below)
- Criteria
- Strongly thrombophilic
- Criteria
- Age <50, no known Thromboembolism Risk Factors or
- Recurrent thromboembolic episode or
- Family History of Thromboembolism
- First degree relative under age 50 years
- Testing
- Evaluation of common causes and
- Evaluation of less common causes (see below)
- Criteria
- Unlikely to be thrombophilic
VI. Labs: Evaluation of common causes ($250)
- Complete Blood Count with Platelets and morphology
- Prothrombin Time
-
Partial Thromboplastin Time
- Lupus Anticoagulant Syndrome suspected if increased PTT that does not correct with 1:1 dilution with normal plasma
-
Connective Tissue Disorder tests
- Test 3-4 weeks after Anticoagulation and acute event resolved and then repeat for confirmation in 12 weeks
- Antiphospholipid Antibody Tests
- Older tests replaced by Antiphospholipid Antibody Tests above
- Antinuclear Antibody Test (ANA)
- Clotting Assay for Lupus Anticoagulant (affected by Anticoagulants)
-
Factor V Leiden or APC Resistance (G1681A)
- Initial: Clotting based assay
- Confirmatory: Factor V Leiden
- Factor II Prothrombin Mutation Analysis (G20210A)
VII. Labs: Evaluation of less common causes ($900)
-
General
- Indicated for strongly thrombophilic patients
- Testing includes all labs above
- Obtain lab testing 2 weeks after off Anticoagulants
- These conditions are highly thrombophilic
- Protein C Levels and Protein S Levels
- Antithrombin III Level (HeparinCofactor assay)
- Other testing to consider
- Plasma Factor VIII Level (increased)
- Fasting Total Plasma Homocysteine Level
- Hyperhomocysteinemia significance in Thrombophilia is in question
- If high Homocysteine then check Methylenetetrahydrofolate reductase (C677T)
VIII. Management
- High Risk Indications for life-long Anticoagulation
- Two or more spontaneous thrombotic events
- One spontaneous life-threatening event
- One spontaneous event with high risk cause
- Antiphospholipid Syndrome
- Antithrombin III Deficiency
- More than one inherited abnormality
- Moderate Risk Indications for event-based prophylaxis
- One event with known provocative stimulus
IX. Resources
- University of Illinois Carle Cancer Center Resources