A 17-year-old girl presents to the emergency department with a headache. The patient has had headaches in the past but this is the worst headache of her life. Her symptoms started yesterday and have been getting progressively worse. The patient states that the pain is mostly on the left side of her head. There has been a recent outbreak of measles at the patient’s school and the patient’s mother has been trying to give her daughter medicine to prevent her from getting sick. Her mother fears that her daughter may have caught measles. Her temperature is 98.6°F (37°C), blood pressure is 123/74 mmHg, pulse is 85/min, and respirations are 13/min. On exam, the patient is an obese girl who is clutching her head with the light in the room turned off. Her neurological exam is within normal limits. Fundoscopic exam reveals mild bilateral papilledema. An MRI of the head is obtained and reveals cerebral edema. A lumbar puncture reveals an increased opening pressure with a normal glucose level. Which of the following is the most likely diagnosis?
Subarachnoid hemorrhage
Fat-soluble vitamin overuse
Migraine headache
Bacterial meningitis
Fat-soluble vitamin overuse
This patient is presenting with headache, bilateral papilledema, obesity, and increased opening pressure on lumbar puncture suggesting a diagnosis of Idiopathic intracranial hypertension (IIH or pseudotumor cerebri). This disease is associated with hypervitaminosis A (a fat-soluble vitamin).

Pseudotumor cerebri classically presents in an obese woman with symptoms of headache and double vision. Overuse of supplements containing vitamin A is a risk factor for developing idiopathic intracranial hypertension. Vitamin A is often used to decrease the duration and severity of a measles infection. On exam, patients will have bilateral papilledema, an increased CSF opening pressure, and cerebral edema. A lumbar puncture is the most accurate diagnostic test for this disease. Treatment is with cessation of offending agents and with carbonic anhydrase inhibitors such as acetazolamide to decrease the rate of cerebrospinal fluid production. Optic nerve sheath fenestration can also be performed in patients who fail medical management.

Fuerst et al. present evidence regarding patients with hypervitaminosis A. They discuss how these patients can present with pseudotumor cerebri. They recommend being vigilant about vitamin A toxicity.

Incorrect Answers:
Answer A: Bacterial meningitis presents with a stiff neck, photophobia, fever, and a CSF finding of low glucose in contrast to this patient’s normal glucose. The most common causes of bacterial meningitis in young adults are N. meningitidis or S. pneumonia. Patients should be treated empirically with ceftriaxone and vancomycin because this is a medical emergency.

Answer C: Migraine headache can present with a unilateral pulsing/pounding headache and photophobia; however, it would not present with physical exam findings of papilledema or cerebral edema. Acute migraines can be treated with NSAIDs and triptan medications. Chronic prophylaxis is with beta-blockers or calcium channel blockers.

Answer D: Subarachnoid hemorrhage presents with the classic, “worst headache of my life,” as this patient has; however, there would be blood visible on MRI which was not described. In addition, there are no symptoms of meningeal irritation from a subarachnoid bleed. Patients may need surgical embolization or clipping of the bleeding vessel.

Answer E: Viral meningitis would present with a stiff neck, photophobia, fever, and CSF that would only demonstrate lymphocytic pleocytosis. Though this patient’s CSF glucose is normal, her other symptoms do not point toward a diagnosis of meningitis. Treatment is either supportive or with antiviral agents depending on the causative organism.

Bullet Summary:
Hypervitaminosis A can cause pseudotumor cerebri, which typically presents in overweight women with headache, double vision, papilledema, and cerebral edema on MRI.