Prevalence of the factor V Leiden mutation in hepatic and portal vein thrombosis.

BACKGROUND The factor V Leiden (FVL) mutation has been shown to be the most frequent cause of hereditary thrombophilia. The prevalence of the mutation in patients with Budd-Chiari syndrome (BCS) and portal vein thrombosis (PVT) has not been fully elucidated. AIMS To investigate the association between the FVL mutation and BCS and PVT. PATIENTS Thirty patients with BCS, 32 patients with PVT, and a control group of 54 patients with liver disorders and no history of thrombosis. METHODS The factor V gene was analysed for the presence of the FVL mutation by a polymerase chain reaction (PCR) technique. The presence of the mutation was confirmed by DNA sequencing. RESULTS Seven (23%) patients with BCS, one (3%) patient with PVT, and three (6%) patients in the control group were identified as having the FVL mutation. There of the BCS patients had coexisting hypercoagulable states. The prevalence of the FVL mutation was significantly higher in patients with BCS compared with patients with PVT and controls (p < 0.04). The FVL mutation was the second most common aetiology associated with BCS. CONCLUSION The FVL mutation is an important factor in the pathogenesis of BCS and screening for the disorder must be included in the investigation of patients presenting with this condition. In contrast, the FVL mutation is not a major predisposing factor in the pathogenesis of PVT.