Cerebral Venous Thrombosis Presenting as a Subacute Headache in a Young Man With Undiagnosed Factor V Leiden Mutation.

Cerebral venous sinus thrombosis (CVT) is a rare but potentially life-threatening condition that presents with non-specific symptoms. This condition is more common in women and can be associated with local infection and hypercoagulable conditions, including protein C and S deficiency, factor V Leiden mutation, anti-thrombin III deficiency, thrombophilia, vasculitis, and malignancy. We report the case of a 24-year-old man who presented with a left temporal headache and right upper and lower extremity paresthesia. He also experienced impaired vision (altered spatial sensation), dental pain, bruxism, nausea, and vomiting. Magnetic resonance imaging and magnetic resonance venography of the brain revealed widespread thrombosis of the cerebral sinuses as well as left superior cerebral cortical veins bilaterally. No evidence of venous infarct was found. Subsequent hematologic evaluation showed the presence of heterozygous factor V Leiden mutation. Testing of family members subsequently revealed the presence of this same mutation in his mother and all three siblings, although there was no family history of stroke, hypercoagulability, or atypical headaches. The patient was started on low-molecular-weight heparin and later transitioned to apixaban. Progression of his headache and visual abnormalities led to the discovery of increased intracranial pressure as demonstrated by papilledema and characteristic findings on computed tomography scan. He was treated with acetazolamide with improvement of his symptoms. CVT is uncommon and can be a diagnostic challenge due to its atypical presentation. Clinicians should consider this diagnosis in patients with a subacute onset of atypical headache, especially when accompanied by seizures, focal neurological deficits, or altered consciousness.