For a patient suspected of having thrombophilia, initial investigations for thrombophilia itself are typically considered after a venous thromboembolism (VTE) event, particularly if it was unprovoked NICE CKS,NICE NG158. Thrombophilia testing involves investigating for acquired or inherited predispositions to venous thrombosis, including deficiencies in natural anticoagulants like antithrombin, protein C, and protein S, or the presence of antiphospholipid antibodies NICE CKS.
- Consider testing for antiphospholipid antibodies in people who have had an unprovoked deep vein thrombosis (DVT) or pulmonary embolism (PE) if there is a plan to stop anticoagulation treatment NICE CKS,NICE NG158.
- Consider testing for hereditary thrombophilia in people who have had an unprovoked DVT or PE and who have a first-degree relative with DVT or PE, especially if there is a plan to stop anticoagulation treatment NICE CKS,NICE NG158.
It is important to note that these tests can be affected by anticoagulants, and specialist advice may be required NICE CKS,NICE NG158.
Thrombophilia testing is generally not offered in the following circumstances:
- To people who have had a provoked DVT or PE NICE CKS,NICE NG158.
- To people who are continuing anticoagulation treatment, as it will not alter management NICE CKS,NICE NG158.
- Routinely to first-degree relatives of people with a history of DVT or PE and thrombophilia NICE CKS,NICE NG158.
As part of the initial management for suspected DVT or PE (which may precede consideration of thrombophilia testing), baseline blood tests are performed. These include a full blood count, renal and hepatic function, prothrombin time (PT), and activated partial thromboplastin time (APTT) NICE CKS,NICE CKS,NICE NG158. These baseline tests are crucial for managing anticoagulation and reviewing medical history, but they are not specific diagnostic tests for thrombophilia itself NICE CKS,NICE CKS,NICE NG158.