Objective: Studies show an association between factor V Leiden and venous thrombosis. Since venous thrombosis is common in Behçet's disease (BD), we looked for an association between thrombosis in BD and the presence of factor V Leiden.
Methods: Twenty-three patients with BD according to International Study Group criteria and 22 patients with rheumatoid arthritis by American College of Rheumatology criteria as controls participated in the study. Patients with BD and controls were tested for the presence of factor V Leiden by polymerase chain reaction (PCR) amplification of genomic DNA and by restriction enzymatic analysis of PCR products.
Results: Three of 23 patients with BD were positive for factor V Leiden (13%). Among BD patients without thrombosis 0/15 were positive; among those with thrombosis 3 of 8 were positive (37.5%) for factor V. Only one patient with RA was positive for factor V Leiden. CONCLUSION. The presence of factor V Leiden in patients with BD may markedly increase the risk of thrombosis.