[Activated protein C resistance in Behçet disease]

Behçet's disease is a systemic condition of unknown cause characterized in 20 to 40% of cases by venous and/or arterial thrombosis that is not fully explained by the hemostasis disorders reported in the literature. The present study investigated resistance to activated protein C in 65 Behçet's disease patients, 75 normal subjects, and 70 patients with a history of isolated thrombosis. The test used involved predilution in factor V-deficient plasma. Activated protein C resistance was found in six Behçet's disease patients (9.2%), eight normal subjects (10.6%), and 21 patients with isolated thrombosis (30%). Of the 26 Behçet's disease patients (40%) with a history of thrombosis, only one had activated protein C resistance. Activated protein C resistance does not explain the increased risk of thrombosis in Behçet's disease patients.