Cerebral Venous Thrombosis Presenting in Pregnancy with Thrombocytosis and Janus Kinase 2 Valine-to-Phenylalanine Mutation

ABSTRACT

A 30-year-old woman in her first pregnancy was admitted with headache and horizontal diplopia indicating left abducens nerve palsy. Brain magnetic resonance imaging revealed a cerebral venous thrombosis. She had thrombocytosis in the peripheral blood, and a genetic test for thrombocytosis revealed the presence of the valine-to-phenylalanine (V617F) mutation of the Janus kinase 2 (JAK2) gene. Treatment with low-molecular-weight heparin resolved her symptoms of headache and diplopia. The presence of genetic disorders such as the JAK2-V617F gene mutation should be assessed in patients with cerebral venous thrombosis and coexisting thrombocytosis.