Coagulation Studies, Factor V Leiden, and Anticardiolipin Antibodies in 40 Cases of Cerebral Venous Thrombosis

BACKGROUND AND PURPOSE: Cerebral venous thrombosis (CVT) is an infrequent condition with a large variety of causes. However, in 20% to 35% of cases, no cause is found. We studied coagulation parameters, including activated protein C resistance associated with factor V gene mutation (factor V Leiden) and anticardiolipin antibodies, in a large series of patients with CVT with or without identified cause or risk factor. METHODS: Forty patients (30 women and 10 men) aged 19 to 71 years (mean age, 36.2 years) with CVT diagnosed by angiography and/or MRI were studied 1 to 18 years after thrombosis. No known cause was found in 10 idiopathic cases. Coagulation studies included the following tests: fibrinogen, antithrombin, protein C, protein S, plasminogen, anticardiolipin antibodies, activated protein C resistance, and factor V Leiden. RESULTS: Six cases of thrombophilia (15%) were found: 1 protein C deficiency, 1 protein S deficiency, and 4 activated protein C resistance with heterozygous factor V Leiden mutation (10%). Only 1 case (protein S deficiency) was found in the group of 10 patients with idiopathic CVT. In the other 5, there was another cause or risk factor. Three patients (8%) had increased anticardiolipin antibodies: 1 with systemic lupus and 2 with primary antiphospholipid syndrome; 2 of these 3 patients also had factor V Leiden mutation. CONCLUSIONS: Although present in a number of CVT cases, acquired (anticardiolipin) or congenital varieties of thrombophilia (factor V Leiden being the most frequent) are almost invariably associated with other predisposing factors. This suggests that (1) these abnormalities should be looked for in patients with CVT, whether a cause is found or not, and (2) their presence should not deter the search for other potential causes. The detection of such abnormalities has major practical consequences on the long-term management of patients to prevent further thrombotic episodes.