How to diagnose Narcolepsy ?
How is narcolepsy diagnosed? Narcolepsy is often diagnosed in adolescence and young adulthood, when falling asleep suddenly in school brings the problem to attention. However, for many people with narcolepsy, the disorder is not diagnosed for up to 10-15 years after symptoms first begin. The disorder may be misdiagnosed as various other conditions or psychological problems. While it is most easily recognized if all the major symptoms are reported, making the diagnosis based solely on symptoms is difficult. People often seek medical help for single symptoms that could be associated with other disorders, particularly epilepsy. In come cases, symptoms are not dramatically apparent for years. Sleep studies are an essential part of the evaluation of people with possible narcolepsy. The combination of an overnight polysomnogram (PSG) followed by a multiple sleep latency test (MSLT) can provide strongly suggestive evidence of narcolepsy, while excluding other sleep disorders. Measurement of hypocretin levels in the cerebrospinal fluid (CSF) may further help to establish the diagnosis. People with narcolepsy often have extremely low levels of hypocretin in their CSF. In some cases, human leukocyte antigen (HLA) typing may be helpful.