Characteristics of patients with cerebral sinus venous thrombosis and JAK2 V617F mutation

Objectives: Janus kinase 2 (JAK2–V617F) mutations can cause thrombocytosis, polycythemia and hyper viscosity leading to cerebral sinus venous thrombosis (CSVT). However, data regarding the characteristics and prevalence of JAK2–V617F mutation in patients with CSVT are currently lacking. We aimed to evaluate the characteristics of CSVT patients that carry the JAK2 mutation. Materials and methods: Data of consecutive patients with CSVT, admitted to three large academic medical centers between 2010 and 2020, were retrospectively studied. Demographics, clinical presentations, radiological and clinical outcome parameters were compared between carriers of the JAK2–V617F mutation and controls. Results: Out of 404 patients diagnosed with CSVT, 26 patients (6.5%) were carriers of the mutation. JAK2 mutation carriers more often had thrombocytosis (54% vs. 1%, p < 0.001). Furthermore, carriers of the JAK2 mutation less often had involvement of the transverse sinus (50% vs. 68%, p = 0.021). Finally, patients with the JAK2 mutation were more prone to have intracerebral hemorrhage (ICH, 31% vs. 17%, p = 0.044), but there was no significant difference between groups in terms of mortality nor functional outcome. Conclusions: JAK2 mutation is not uncommon in patients with CSVT and should be routinely screened for in this population. CSVT in JAK2 mutation carriers may have a tendency toward involving specific venous sinuses and is associated with a higher rate of ICH but similar overall prognosis.