Referred Tests
| Web: | mayocliniclabs.com |
|---|---|
| Email: | mcl@mayo.edu |
| Telephone: | 800-533-1710 |
| International: | +1 855-379-3115 |
| Values are valid only on day of printing. | |
Test ID: ORXNA
Orexin-A/Hypocretin-1, Spinal Fluid
Useful For 
Suggests clinical disorders or settings where the test may be helpful
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.
Highlights
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.
Method Name A short description of the method used to perform the test
Radioimmunoassay (RIA)
NY State Available Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name Lists a shorter or abbreviated version of the Published Name for a test
Aliases Lists additional common names for a test, as an aid in searching
Orexin
Hypocretin-1
Orexin-A