Familial narcolepsy

Narcolepsy is a disease characterized by chronic excessive daytime sleepiness with episodic sleep attacks. There are several associated symptoms of narcolepsy: cataplexy (bilateral muscle weakness without loss of consciousness, provoked by an emotional trigger, e.g. laughter), sleep paralysis (isolated loss of muscle tone associated with rapid eye movement [REM] in normal sleep) and hypnagogic-hypnopompic hallucinations (vivid dreaming occurring at the time of sleep onset and awakening that can be difficult to distinguish from reality).

The authors present eleven patients with suspected narcolepsy, who were members of a five-generation family with many cases of episodic excessive daytime sleepiness. Some of them experienced sleep attacks which were occasionally associated with a sudden loss of muscle tone (cataplexy), as well as with sleep paralysis and hypnagogic hallucinations. All probands had magnetic resonance (MR) of the brain performed, along with routine blood tests, EEG, polysomnography, examination of the level of hypocretin in the cerebrospinal fluid and evaluation by means of Epworth and Stanford Sleepiness Scales.

Narcolepsy was diagnosed in nine patients. Improvement in their clinical state was observed during the treatment with modafinil.