Should We Screen for Janus Kinase 2 V617F Mutation in Cerebral Venous Thrombosis?

BACKGROUND: The presence of Janus Kinase 2 (JAK2) V617F mutation represents a major diagnostic criterion for detecting myeloproliferative neoplasms (MPN) and even in the absence of overt MPN, JAK2 V617F mutation is associated with splanchnic vein thrombosis. However, the actual prevalence and diagnostic value of the JAK2 V617F mutation in patients with cerebral venous thrombosis (CVT) are not known. The aims of this study were to assess the prevalence of JAK2 V617F mutation in a large group of consecutive CVT patients, to detect clinical, biological, and radiological features associated with the mutation, and to determine the long-term venous thrombosis recurrence rate in CVT patients with JAK2 mutation but without overt MPN in order to recommend the best preventive treatment. METHODS: This was a prospective study conducted on consecutive patients with a first-ever radiologically confirmed CVT. JAK2 V617F mutation analysis was assessed in all the study subjects. JAK2 V617F-positive patients were followed up to detect new venous thrombotic events. RESULTS: Of the 125 included subjects, 7 were found to have JAK2 V617F mutation (5.6%; 95% CI 2.3-11.2). Older age (p = 0.039) and higher platelet count (p = 0.004) were independently associated with JAK2 V617F positivity in patients without overt MPN. During a mean follow-up period of 59 (SD 46) months, 2 JAK2 V617F-positive patients presented with 4 new venous thromboembolic events. CONCLUSIONS: Screening for the JAK2 V617F mutation in CVT patients seems to be useful even in the absence of overt MPN and/or in the presence of other risk factors for CVT because of its relatively high prevalence and the risk of thrombosis recurrence.

Venous Thrombotic Recurrence After Cerebral Venous Thrombosis: A Long-Term Follow-Up Study.

BACKGROUND AND PURPOSE: After cerebral venous thrombosis (CVT), the risk of venous thrombotic events was estimated at 2% to 3% for a new CVT and 3% to 8% for extracranial events. However, because of the paucity of prospective studies, the clinical course of CVT is still largely unknown. We aimed to prospectively evaluate the rate of thrombosis recurrence in a cohort of CVT patients with a long-term follow-up and to detect predisposing factors for recurrence. METHODS: Consecutive CVT patients with complete clinical, radiological, biological, and genetic data were systematically followed up. New venous thrombotic events were detected after hospital readmission and imaging confirmation. RESULTS: One-hundred eighty-seven patients (mean age 45±18 years, 67% women) with angiographically confirmed CVT were included. Cause was found in 73% of patients. Coagulation abnormality and JAK2 gene mutation were detected in 20% and 9%, respectively. Median follow-up length was 73 months (range 1-247 months). Mean duration of the oral anticoagulant treatment was 14 months. Mortality rate was 2.5% per year, with 2% in-hospital mortality. During follow-up, CVT reoccurred in 6 patients, whereas 19 subjects had a symptomatic extracranial venous thrombotic event, with cumulative venous thrombotic recurrence rates of 3% at 1 year, 8% at 2 years, 12% at 5 years, and 18% at 10 years. A previous venous thrombotic event (hazard ratio, 2.8; P=0.018), presence of cancer or malignant hemopathies (hazard ratio, 3.2; P=0.039), and unknown CVT causes (hazard ratio, 2.81; P=0.024) were independently associated with recurrence. CONCLUSIONS: In our cohort of CVT patients followed on average for >6 years, subjects with a previous venous thrombotic event, cancer/malignant hemopathies, and unknown CVT causes were found to be at higher risk of recurrence.