Thrombophilia Testing: from Genetic Predisposition to Discrimination

Venous thromboembolism (VTE) is a multifactorial disease arising from a complex interplay between acquired clinical risk factors and inherited genetic predispositions. VTE is a common condition and occurs in 1 to 2 per 1,000 people every year in Western countries.[1] [2] Laboratory tests for inherited thrombophilia are frequently requested with the goal to uncover the susceptibility to VTE in patients devoid of major clinical risk factors. Conventional thrombophilia testing typically involves the determination of deficiencies in antithrombin, protein C, or protein S, and genetic testing for the factor V Leiden (FVL) and prothrombin G20210A variants.[3] However, despite their widespread use, these tests are critically flawed with limited sensitivity and specificity for VTE, as well as with methodological issues. Moreover, conventional thrombophilia tests fail to differentiate between patients at high and low risk of VTE recurrence.[4] [5] [6] Additionally, thrombophilia testing introduces risks, with potential long-term personal consequences, if the information is misinterpreted or inappropriately applied. As a consequence, current guidelines recommend against the routine use of thrombophilia tests.[7] [8] [9] [10] Nonetheless, there is substantial nonadherence to the guidelines in clinical practice. In a recent, large, single-center cross-sectional study, merely one-third of thrombophilia tests were conducted according to the guidelines.[11] Furthermore, the study underscored the limited therapeutic value, with only 8.3% of thrombophilia tests influencing anticoagulant treatment decisions.[11]

To underscore the importance of judicious use of thrombophilia tests and to highlight their potential psychological and social consequences, we here present three unrelated cases of genetic discrimination after testing for inherited thrombophilia. The cases were selected from the outpatient clinic of the Thrombosis and Haemostasis Department at the University Hospitals Leuven, Belgium. All three patients presented between 2020 and 2023 after medical disqualification by the police department based on the results of previous thrombophilia tests. To the best of our knowledge, no additional cases of discrimination resulting from thrombophilia testing were documented at our institution. The retrospective study of our cases was approved by the Ethics Committee Research UZ/KU Leuven. Informed consent for publication was obtained from all three patients.

Publication History

Received: 14 December 2023

Accepted: 05 March 2024

Accepted Manuscript online:
09 March 2024

Article published online:
08 April 2024

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