title: Narcolepsy in a three-year-old girl: A case report.
abstract: OBJECTIVE
  Narcolepsy is characterized by excessive daytime somnolence associated with sleep paralysis, hallucinations when falling asleep or awakening, and cataplexy. Early recognition of pediatric narcolepsy is essential for growth and development. We experienced a case of narcolepsy in a three-year-old girl.
  
  
  METHODS
  The patient underwent brain MRI and 24h video-electroencephalogram (EEG) monitoring. Polysomnography (PSG) with multiple sleep latency test (MSLT) and human leukocyte antigen (HLA) DQ typing was performed.
  
  
  RESULTS
  The brain MRI was normal. 24h video-EEG monitoring revealed no abnormal slow or epileptiform discharge on interictal EEG, and no EEG change during tongue thrusting, dropping head with laughter, or flopping down, which was consistent with cataplexy associated with narcolepsy. A mean sleep latency of 2.5 min and four episodes of sleep-onset REM periods in five naps were observed in PSG with MSLT. She was positive in HLA-DQB1*0602. Based on these findings, she was diagnosed as narcoleptic with cataplexy.
  
  
  CONCLUSIONS
  The history, combined with PSG and MSLT, was helpful in the diagnosis of narcolepsy. We report a case of early-onset narcolepsy presenting with excessive sleepiness and cataplexy.
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Eu Gene
authors.initials: EG
authors.lastname: Park
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Jiwon
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Eun Yeon
authors.initials: EY
authors.lastname: Joo
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Munhyang
authors.initials: M
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea. Electronic address: jhlee0101@skku.edu.
authors.forename: Jeehun
authors.initials: J
authors.lastname: Lee
mesh_terms: D001921:Brain / Q000503:physiopathology; D002675:Child, Preschool; D003937:Diagnosis, Differential; D004569:Electroencephalography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D009290:Narcolepsy / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology* / Q000628:therapy
keywords: Cataplexy; Narcolepsy; Toddler