Plasma von Willebrand factor, tissue plasminogen activator, plasminogen activator inhibitor, and antithrombin III levels in Behçet's disease.

Sixty-three patients with Behçet's disease (BD), 30 patients with recurrent oral ulcer and 30 healthy individuals as control group were included in the study. ISG criteria was used for the diagnosis of BD and patients were classified as active and inactive and evaluated accordingly. In the patient and control groups, von Willebrand factor (vWF), tissue plasminogen activator (tPA), and plasminogen activator inhibitor (PAI) levels were determined using ELISA method and antithrombin III (AT-III) by nephelometric methods. High levels of endothelial product, vWF in the active Behçet patient group (p < 0.005) supports endothelial destruction due to vasculitis related with BD. In the active patient group tPA levels were significantly lower (p < 0.05) than the inactive and control groups with higher levels of PAI (p < 0.05 and p < 0.01) respectively. In Behçet disease, besides the decrease in tPA synthesis, high PAI levels also can affect tPA decrease and lead to inhibition of fibrinolytic activity. In active Behçet group, levels of AT-III were low and no significant difference was observed in recurrent oral ulcer and control groups. This situation may arise from the excessive use of AT-III in active disease. In conclusion, high levels of vWF in Behçet patients is thought to arise from vasculitis and high levels of PAI from the accumulation of thrombocytes on the damaged surface of endothelium leading to a decrease in tPA levels and inhibition of fibrinolytic activity.