Abstract TP229: Cerebral Venous Thrombosis Caused by Congenital Thrombophilia in Japan

Background: Cerebral venous thrombosis is an uncommon type of stroke that sometimes affects young to middle-aged patients. Various conditions can cause CVT, including drugs, infection, dehydration, pregnancy, malignancies, and acquired and congenital thrombophilia. Hereditary thrombophilia caused by genetic mutation, such as antithrombin, protein C (PC) and protein S (PS), requires warning about the risk and signs of thrombosis recurring. Because CVT itself is a rare disease, it’s sometimes difficult to diagnosis the hereditary thrombophilia in each case. This study describes the clinical features and causes related to CVT in Japan, and elucidates the characteristics of CVT caused by hereditary thrombophilia. Methods: We enrolled 40 patients (24 males, 16 females, age: 18-81 years) diagnosed CVT confirmed by either magnetic resonance venography, enhanced computed tomography, or angiography. Demographic data and clinical features were recorded and compared. Results: Eleven patients (6 males, 5 females, age: 27-71 years) were diagnosed CVT due to congenital thrombophilia, and the other twenty-nine patients (18 males, 11 females, age: 18-81 years) were not. Congenital thrombophilia included five patients with PS gene mutation, three with PC gene mutation, two with antithrombin gene mutation, and one alpha fibrinogen gene mutation. Although we failed to detect a significant statistical difference between congenital thrombophilia patients and others with regards to age, sex, symptoms, vein of occlusion, d-dimer levels, activity levels of PS and PC were significantly decreased in congenital thrombophilia patients. Discussion: Cerebral venous thrombosis in Japanese patients is frequently associated PS or PC gene mutations. This study showed CVT caused by congenital thrombophilia had low activity of PS and PC. Clinicians should aware the presence of PS or PC gene mutations during the treatment of CVT and check the PS and PC activity.