Narcolepsy caused by acute disseminated encephalomyelitis.

Background: Narcolepsy with cataplexy is caused by a selective loss of hypocretin-producing neurons, but narcolepsy can also result from hypothalamic and rostral brainstem lesions.

Patient: We describe a 38-year-old woman with severe daytime sleepiness, internuclear ophthalmoplegia, and bilateral delayed visual evoked potentials. Her multiple sleep latency test results demonstrated short sleep latencies and 4 sleep-onset rapid eye movement sleep periods, and her cerebrospinal fluid contained a low concentration of hypocretin. Magnetic resonance imaging showed T2 and fluid-attenuated inversion recovery hyperintensity along the walls of the third ventricle and aqueduct, which are consistent with acute disseminated encephalomyelitis.

Results: After treatment with steroids, this patient's subjective sleepiness, hypersomnia, and hypocretin deficiency partially improved.

Conclusions: Autoimmune diseases such as acute disseminated encephalomyelitis can produce narcolepsy. Most likely, this narcolepsy is a consequence of demyelination and dysfunction of hypocretin pathways, but direct injury to the hypocretin neurons may also occur.