Thrombophilia Workup - Indications

This is a controversial subject!
  
Times to consider workup for inherited thrombophilia: Unprovoked DVT with young age, family history of VTE, recurrent thrombosis, unusual location (e.g. cerebral sinus thrombosis), or massive presentation (i.e. massive unprovoked PE). 
  
The big 5 Inherited Thrombophilias are:

1. Factor V Leiden (Active protein C resistance)
2. Prothrombin mutation
3. Protein C deficiency
4. Protein S deficiency
5. Antithrombin III deficiency  **for Protein C/S and AT III deficiency, do NOT check acutely as these are affected by VTE and anticoagulation**

In addition, consider looking for Antiphospholipid syndrome with anticardiolipin Abs and lupus anticoagulant.
  
** Realize that the utility of screening for inherited thrombophilias is controversial.** 

• Arguments for screening: may have implications for family member screening (i.e. if family member screens positive, may help prevent VTE by avoiding OCPs, HRT, etc); also, there is some evidence that if you have multiple defects, you may well have a significantly higher risk of recurrence.
• Arguments against screening: includes the high costs of the tests and the uncertainty regarding whether or not this should affect management, i.e. does having one of these thrombophilias truly affect the risk of recurrence and do they need to be anticoagulated for longer?

(Chanu Rhee MD, 9/17/10)