[No Indication for Thrombophilia Screening in Patients with Idiopathic Venous Thromboembolism and Their Relatives]

In 70% to 80% of patients with venous thromboembolism, a thrombophilic defect can be identified. The most important defects are: antibodies to phospholipids or lupus anticoagulants, mutation of factor V Leiden, prothrombin mutation, mild hyperhomocysteinaemia, and increased factor VIII levels. Deficiencies of antithrombin, protein C or protein S are rare. Whether or not screening for thrombophilia in patients with idiopathic venous thromboembolism is justified, depends on the potential benefits for the patients, or their relatives. At present, patients with a thrombophilic defect do not appear to have a much higher risk for recurrent venous thromboembolism, than patients with thrombosis but without a defect. The absolute risks of venous thromboembolism in asymptomatic relatives with a thrombophilic defect are too low to justify initiating a general policy of family screening. In conclusion, a conservative approach towards thrombophilia screening in idiopathic venous thromboembolism is warranted.