Inherited thrombophilic abnormalities and risk of portal vein thrombosis. a meta-analysis.

Inherited thrombophilic abnormalities may have a role in the development of portal vein thrombosis (PVT). However, the prevalence of these factors in patients with PVT has been evaluated only in small studies with non-conclusive results. It was the purpose of this study to assess the risk of PVT associated with factor V Leiden (FVL) and G20210A prothrombin mutation (PTM). The MEDLINE, EMBASE, Cochrane Library databases, reference lists of retrieved articles and contact with content experts were used. Studies carried out in Western Europe comparing the prevalence of prothrombotic abnormalities in patients with PVT and in controls without a history of thromboembolic disease were included. Two reviewers independently selected studies and extracted study characteristics, quality and outcomes. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each trial and pooled using a fixed and random-effects model. Statistical heterogeneity was evaluated using the I(2) statistic. Sensitivity analyses were performed examining separately studies according to the etiology of PVT and to control population. Twelve studies involving more than 3,000 patients were included. The pooled OR for PVT was 1.90 (95%CI: 1.25, 2.90) in patients with FVL and 4.48 (95%CI: 3.10, 6.48) in patients with PTM. In conclusion, PVT is associated with the presence of FVL and PTM in Western Europe.