Fatal pulmonary artery thrombosis in a patient with Behçet's disease, activated protein C resistance and hyperhomocystinemia.

Behçet's disease (BD) is known for its tendency for thromboembolism, which is thought to be due to vascular injury. The important role of inherited thrombophilias is now becoming increasingly clear. However, conflicting data exist in terms of the contribution of these factors to the thrombotic risk in BD. In this case report, we describe a patient with BD who presented with severe cor pulmonale due to recurrent chronic venous thromboembolism and pulmonary artery thrombosis. The biochemical evaluation revealed that the patient was homozygotic for the factor V Leiden (R506Q) mutation and had increased levels of homocysteine. His condition deteriorated despite adequate anticoagulation treatment, and he died suddenly after 7 months of follow-up. We assume that the presence of thrombophilic risk factors augments and synergizes with the hypercoagulable state already existing in BD, leading to fatal thrombosis in this patient.