- HOME
- Vol.42 No.3
- CLINICA NEUROL, 42: 233－236, 2002
- Vol.42 No.3 contents
Case Report
Narcolepsy manifesting initially as cataplexy and sleep paralysis: Usefulness of CSF hypocretin-1 examination for early diagnosis
Yuka Kobayashi, M. D. 1), Masayuki Miyamoto, M. D. 1), Tomoyuki Miyamoto, M. D. 1), Kaoru Yamazaki, M. D. 1), Koichi Hirata, M. D. 1), Takashi Kanbayashi, M. D. 2) and Tetsuo Shimizu, M. D. 2)
1)Department of Neurology Dokkyo University School of Medicine
2)Department of Neuropsychiatry Akita University School of Medicine
We report a 24-year-old man with narcolepsy initially suffered from cataplexy and sleep paralysis. From May 2000, at age 23 he experienced two kinds of recurrent episodes of weakness without altered consciousness; one was provoked by emotion and excitement, the other occurred spontaneously on onset of sleep without hallucination. He denied having daytime sleepiness and did not experience hypnagogic hallucinations. In July 2000, at our hospital he received the first medical examinations, of which physical and neurological results were unremarkable. A magnetic resonance imaging scan of the brain also gave unremarkable results. The initial diagnosis was epilepsy, and anti-convulsant drugs were begun in August 2000. The weakness episodes were not lessened by the treatment with carbamazepine, sodium valproate or clonazepam, and he was admitted to our clinic in April 2001 for further examinations. Human leukocyte antigen testing was positive for DR15 (DR2) and DQ6 (DQ1). The routine electroencephalographam detected no epileptic discharge or paradoxical α blocking. A polysomnogram showed a sleep onset REM sleep period and sleep fragmentation, but there was no apnea or periodic leg movements. A multiple sleep latency test showed a mean sleep latency of 1.8 min and REM sleep in three of five naps. These findings suggested probable narcolepsy, so we examined the hypocretin-1 (orexin A) concentration in his cerebrospinal fluid (CSF). It was below the detection limit of the assay (<40pg/mL). The final diagnosis in April 2001 was narcolepsy. Making an initial diagnosis of incomplete or atypical narcolepsy is difficult for clinicians. A delay in diagnosis, however, may produce personal and social problems for narcoleptic patients. We believe that an examination of CSF hypocretin-1 aids in the early diagnosis of narcolepsy.
(CLINICA NEUROL, 42: 233－236, 2002)
key words: narcolepsy, cataplexy, sleep paralysis, episodes of weakness, hypocretin-1 (orexin A)
(Received: 5-Feb-02)
