Hypocretinergic dysfunction in neuromyelitis optica with coma-like episodes.

Devic's neuromyelitis optica (NMO) is a severe demyelinating disease of the central nervous system, often misdiagnosed as multiple sclerosis, and involving mainly optic nerves and the spinal cord. We report on a peculiar case of relapsing NMO with severe recurrent dysautonomia and hypersomnia, in which we had the opportunity to observe a dramatic decrease in hypocretin/orexin cerebrospinal fluid level.