Coexisting narcolepsy (with and without cataplexy) and multiple sclerosis : Six new cases and a literature review.

Narcolepsy and MS are rarely associated. In addition to NwC secondary to hypothalamic demyelination, some patients present a coexistence of MS with NC without detectable hypothalamic lesions. The rarity of reports on this association probably reflects underrecognition. The elucidation of underlying genetic and immune mechanisms needs further studies.