Veneuze trombo-embolie: Wanneer zijn laboratoriumtesten voor trombofilie zinvol?

After venous thromboembolism laboratory tests for thrombophilia are often ordered. However, when results are abnormal, clinical consequences (i.e. prolonged treatment with anticoagulants) are not always clear. In the new Dutch guideline on 'diagnosis, prevention and treatment of venous thromboembolism and secondary prevention of arterial thrombosis' recommendations are given for situations where laboratory testing for thrombophilia is useful and affects clinical decisions. In this article the consequences of this guideline for the clinical laboratories are summarised. Generally, for most patients with primary or recurrent venous thromboembolism, tests for thrombophilia other than anti-phospholipid antibodies are not recommended. In exceptional cases where thrombophilia tests can be considered, one should realise that preanalytical parameters can influence test results.