Valerio De Stefano, MD, Institute of Hematology, Catholic University, Largo Gemelli 8, 00168 Rome, Italy, Tel.: +39 06 30154968, Fax: +39 06 30154206, E-mail:
Thromb Haemost. 2013 Oct;110(4):697-705. doi: 10.1160/TH13-01-0011. Epub 2013 Jul 11.
The clinical penetrance of venous thromboembolism (VTE) susceptibility genes is variable, being lower in heterozygous carriers of factor V Leiden and prothrombin 20210A (mild thrombophilia), and higher in the rare carriers of deficiencies of antithrombin, protein C or S, and those with multiple or homozygous abnormalities (high-risk thrombophilia). The absolute risk of VTE is low, and the utility of laboratory investigation for inherited thrombophilia in patients with VTE and their asymptomatic relatives has been largely debated, leading to the production of several Guidelines from Scientific Societies and Working Groups. The risk for VTE largely depends on the family history of VTE. Therefore, indiscriminate search for carriers is of no utility, and targeted screening is potentially more fruitful. In patients with VTE inherited thrombophilia is not scored as a determinant of recurrence, playing a minor role in the decision of prolonging anticoagulation; indeed, a few guidelines consider testing worthwhile to identify carriers of high-risk thrombophilia, particularly those with a family history of VTE. The identification of the asymptomatic carrier relatives of the probands with VTE and thrombophilia could reduce cases of provoked VTE, offering them primary antithrombotic prophylaxis during risk situations. In most guidelines, this is considered justified only for relatives of probands with a deficiency of natural anticoagulants or multiple abnormalities. Counselling the asymptomatic female relatives of individuals with VTE and/or thrombophilia before pregnancy or the prescription of hormonal treatments should be administered with consideration of the risk driven by the type of thrombophilia and the family history of VTE.
静脉血栓栓塞症 (VTE) 易感性基因的临床外显率各不相同，携带因子 V 莱顿和凝血酶原 20210A 杂合子的患者（轻度血栓形成倾向）外显率较低，而抗凝血酶、蛋白 C 或 S 缺乏症的罕见携带者以及携带多种或纯合异常的患者（高危血栓形成倾向）外显率较高。VTE 的绝对风险较低，并且在 VTE 患者及其无症状亲属中，实验室检查遗传性易栓症的实用性已受到广泛争议，导致来自科学学会和工作组的多个指南出台。VTE 的风险在很大程度上取决于 VTE 的家族史。因此，对携带者的盲目筛查没有用处，而有针对性的筛查可能更有成效。在 VTE 患者中，遗传性易栓症不被视为复发的决定因素，在延长抗凝治疗的决策中作用较小；实际上，一些指南认为值得进行检测，以识别高危血栓形成倾向的携带者，特别是那些有 VTE 家族史的携带者。VTE 和易栓症患者的无症状携带者亲属的识别可以减少诱发性 VTE 病例，并在高危情况下为他们提供初级抗血栓预防。在大多数指南中，只有当缺乏天然抗凝剂或存在多种异常的先证者的无症状亲属才被认为是合理的。在 VTE 和/或易栓症患者的无症状女性亲属怀孕前或处方激素治疗前，应根据血栓形成倾向的类型和 VTE 的家族史所带来的风险进行咨询。
