CSF hypocretin-1 (orexin-A) levels in childhood narcolepsy and neurologic disorders

Hypersomnia and cataplexy expression in childhood narcolepsy are often different from adult cases, making diagnosis difficult.1 The Multiple Sleep Latency Test (MSLT) for demonstrating hypersomnia and sleep-onset REM periods has not been standardized for children under age 82 and has limited value in pediatrics. CSF hypocretin-1 measurements were established as a new diagnostic tool for narcolepsy–cataplexy in adults3–5⇓⇓ but has not yet been evaluated in children.4 We measured CSF hypocretin-1 levels in 132 children with various neurologic disorders (including six narcoleptic children) to evaluate the diagnostic value of CSF hypocretin measures for childhood narcolepsy. We analyzed previously collected data, gathered from 1992 to 2003 for diagnostic and research purposes, including CSF samples (n = 132, including 14 cases previously reported), collected from patients (under age 20 from seven Japanese hospitals) with neurologic disorders (the core experimental protocol was approved at Akita University in August 2002; the local ethical committee approved the use of CSF samples). Patients were categorized based on the diagnosis determined by …