When should I consider referring a patient with Factor V Leiden for specialist hematology assessment?

Consider referring a patient with Factor V Leiden mutation for specialist hematology assessment if they have had an unprovoked venous thromboembolism (VTE), especially deep vein thrombosis (DVT) or pulmonary embolism (PE), and there is a first-degree family history of VTE. This is because thrombophilia testing, including for Factor V Leiden, is clinically useful in such cases to guide the duration and intensity of anticoagulation treatment and to assess recurrence risk.

Referral is also recommended for women with Factor V Leiden mutation who are planning pregnancy or are pregnant, particularly if they have a history of VTE or an abnormal thrombophilia screen, to enable specialist pre-conception counselling and management planning.

Testing and referral are generally not indicated for patients with provoked VTE or those continuing anticoagulation treatment where management would not change.