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Values are valid only on day of printing. |
Aiding in the diagnosis and differentiation of type 1 narcolepsy from other causes of hypersomnolence
This assay is not intended for use as a screening test.
Orexin-A (hypocretin-1) is a neuropeptide involved in the sleep/wake cycle in humans. An abnormally low concentration of orexin-A (hypocretin-1) in cerebrospinal fluid (CSF) indicates type I narcolepsy.
The diagnostic criteria for type 1 narcolepsy in the third edition of the International Classification of Sleep Disorders (2014) include the presence of hypersomnia, cataplexy (episodes of muscle weakness in response to emotional stimuli) and/or measured CSF orexin (hypocretin-1) concentrations less than or equal to 110 pg/mL .
CSF concentrations have been found to almost always be above 200 pg/mL in healthy individuals and those with non-type 1-narcoleptic sleep disorders such as narcolepsy type 2 and idiopathic hypersomnia.
Radioimmunoassay (RIA)