Pseudotumor cerebri syndrome in a patient with narcolepsy type 1

Type 1 narcolepsy (NT1) is a chronic primary disorder of hypersomnolence characterized by excessive daytime sleepiness, cataplexy, sleep paralysis, hypnagogic hallucinations and disrupted nocturnal sleep. NT1 is linked to hypothalamic hypocretin deficiency, strongly associated with Human Leukocyte Antigen (HLA) marker DQB1*06:02 and of probable autoimmune origin. NT1 is usually associated with increased rates of overweight and obesity, and sometimes with increases in overnight blood pressure and increased rates of hypoventilation with raised CO₂ levels overnight. Many of these are predisposing factors for pseudotumor cerebri syndrome (PTCS). We present a case of a young girl with both NT1 and PTCS that responded well to treatment with acetazolamide after early identification, with improvement of headache and resolution of hypoventilation.