Thrombophilia and Transient Risk Factors for Venous Thromboembolism in Women with Distal Deep Vein Thrombosis

Abstract

We retrospectively investigated consecutive women aged 12–49 years diagnosed with VTE and referred to our Thrombosis Center to be investigated for thrombophilia screening in the last 3 years. DVT was objectively confirmed by bilateral B-mode compression ultrasound and PE by ventilation/perfusion lung scan, computed tomography or angiography. Patients underwent objective investigation for PE only if they had pulmonary symptoms, whereas patients with symptomatic PE underwent objective investigation for DVT. DVT of the calf vein was considered distal, thrombosis involving the remaining vein segments was considered proximal. The transient risk factors considered were: surgery, trauma, leg cast, oral contraceptives, hormonal replacement therapy, pregnancy and puerperium. We previously described the methods used for thrombophilia screening [9] . All subjects gave their informed consent to participate in the study in accordance with the Local Ethics Committee Recommendations. We analyzed the presence of consensual thrombophilia and transient risk factors in 47 women with distal DVT complicated (n = 6) by PE or not (n = 41), 47 with proximal DVT complicated (n = 5) by symptomatic PE or not (n = 42), and 21 women with isolated PE. Women with isolated PE were younger at the time of the first event (mean age 24.5 years) than those with Dear Sir, Although deep vein thrombosis (DVT) and its major complication, pulmonary embolism (PE), are usually considered a single disease entity, venous thromboembolism (VTE) has a wide spectrum of clinical manifestations. A variety of risk factors may play different roles in determining the various locations of thrombi [1] . For example, the factor II 20210A (FII20210A) polymorphism has been reported to be more than twice as common in patients with cerebral venous sinus thrombosis than in patients with DVT [2] . Several studies have provided evidence for a reduced incidence of PE in relation to DVT in patients with the factor V Leiden (FVL) mutation [3–5] . Recently, 3 studies accessing the rate of thrombophilia and the location of lower-extremity DVT reported discordant results [6–8] . Patients with a deficiency in antithrombin (AT), protein C (PC) or protein S (PS), or a high level of factor VIII (FVIII) were excluded from these studies. In the present study, we investigated whether thrombophilic defects including AT, PC, PS deficiency or a high FVIII level play a different role in patients presenting with isolated PE, distal or proximal DVT. We also analyzed the association between the presence of transient risk factors at the time of VTE and the location of VTE.