A 16-year-old boy is brought to the clinic for evaluation of headaches. For the last month, he has had daily, throbbing pain in the frontal region that is worse in the morning and occasionally associated with nausea and vomiting. Acetaminophen provides some relief. The patient also had several brief episodes of blurriness in his left eye during football practice last week. In addition to acetaminophen, he takes oral isotretinoin for severe acne. Temperature is 36.7 C (98.1 F), blood pressure is 130/80 mm Hg, pulse is 70/min, and respirations are 15/min. The patient is sitting up and cooperative with the examination. The pupils are equal and reactive to light. Eye examination shows bilateral optic disc edema and decreased visual acuity. The visual fields are full. There is no neck stiffness. Motor examination reveals 5/5 strength, 2+ deep tendon reflexes, and a normal plantar response. Sensory examination is unremarkable. Which of the following is the most likely cause of this patient's symptoms?

Question

A 16-year-old boy is brought to the clinic for evaluation of headaches.  For the last month, he has had daily, throbbing pain in the frontal region that is worse in the morning and occasionally associated with nausea and vomiting.  Acetaminophen provides some relief.  The patient also had several brief episodes of blurriness in his left eye during football practice last week.  In addition to acetaminophen, he takes oral isotretinoin for severe acne.  Temperature is 36.7 C (98.1 F), blood pressure is 130/80 mm Hg, pulse is 70/min, and respirations are 15/min.  The patient is sitting up and cooperative with the examination.  The pupils are equal and reactive to light.  Eye examination shows bilateral optic disc edema and decreased visual acuity.  The visual fields are full.  There is no neck stiffness.  Motor examination reveals 5/5 strength, 2+ deep tendon reflexes, and a normal plantar response.  Sensory examination is unremarkable.  Which of the following is the most likely cause of this patient's symptoms?

Quizplus · Accepted Answer

11ec25c8_d6f2_8e68_bc81_df5fd1995a84_MD0003_00 This patient's headache and vision changes are consistent with intracranial hypertension secondary to isotretinoin. Excessive vitamin A and its metabolites (eg, isotretinoin) are believed to impair cerebrospinal fluid reabsorption, leading to increased intracranial pressure (ICP). Other medications that can increase ICP include tetracyclines and growth hormone. The initial symptom of intracranial hypertension is usually a throbbing headache that is worse with lying flat (which elevates ICP) and improves with standing (which lowers ICP). Headache may be accompanied by pulsatile tinnitus (ie, "whooshing" sound), nausea, vomiting, and/or blurry vision. Optic disc edema (papilledema) is characteristic of intracranial hypertension. Decreased visual acuity and cranial nerve palsies (most commonly of the abducens nerve [CN VI]) may also be present. Diagnostic workup includes neuroimaging (preferably MRI with MR venography) to rule out a mass or obstruction as the cause of increased ICP. On lumbar puncture, an elevated opening pressure (>250 mm H₂O) with an otherwise normal cerebrospinal fluid analysis is diagnostic. Withdrawal of the offending medication usually leads to resolution of symptoms. (Choice A) Cluster headaches are excruciating, unilateral headaches that occur near the eye or temporal region. They are most common in men age 20-50. Papilledema does not occur with cluster headaches. (Choice C) Optic chiasm glioma can cause insidious headache and vision changes. However, with a tumor compressing the optic chiasm, a visual field defect (eg, bitemporal hemianopsia) would be expected. (Choice D) Optic neuritis usually presents with acute vision loss and eye pain. Optic disc swelling can occur due to papillitis but is typically unilateral and not associated with morning headache and vomiting. (Choice E) Viral encephalitis may present with fever, headaches, neurologic deficits, and altered mental status. It is unlikely in this patient who is afebrile and has normal mental status. Educational objective: Intracranial hypertension presents with headache, vision changes, papilledema, and/or abducens nerve (CN VI) palsy. Growth hormone, tetracyclines, and excessive vitamin A and its derivatives (eg, isotretinoin) can cause increased intracranial pressure. Withdrawal of these medications leads to symptom resolution. References: Medication-related pseudotumor cerebri syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/27786584)

A 16-Year-Old Boy Is Brought to the Clinic for Evaluation