title: Benign neonatal sleep myoclonus: our experience of 15 Japanese cases.
abstract: OBJECTIVE
  Benign neonatal sleep myoclonus is a non-epileptic movement disorder that may mimic neonatal seizures. The aim of this study was to clarify the clinical manifestations and outcomes in Japanese infants with benign neonatal sleep myoclonus.
  
  
  METHODS
  We reviewed the clinical manifestations and outcomes in 15 consecutive patients with benign neonatal sleep myoclonus (males: 10), including three paired familial cases, referred to our center between 1996 and 2011. The diagnosis of benign neonatal sleep myoclonus was based on a neonatal onset, characteristic myoclonic jerks that occurred during sleep, and normal electroencephalogram findings.
  
  
  RESULTS
  All were healthy full-term neonates at birth. The age at onset ranged from 1 to 18 days (median: 7 days). Prior to referral to our center (3-8 weeks), two infants had been placed on antiepileptic drugs, without effects. During the clinical course, the myoclonic jerks resolved by 6 months in 14 of the 15 patients. On follow-up (final evaluation, mean: 38 months), all but one patient (speech delay) showed normal development. None developed epilepsy. Of note, migraine occurred after 5 years of age in three children, including one who developed cyclic vomiting syndrome, evolving to migraine. Another boy developed cyclic vomiting syndrome, a precursor of migraine, before 1 year, and was being followed. A high incidence of migraine was observed in five (42%) of 12 parents whose detailed family history was available.
  
  
  CONCLUSIONS
  Our study suggests that benign neonatal sleep myoclonus is related to migraine. With the high rate of familial cases, further genetic study, including migraine-related gene analysis, is necessary to determine the underlying mechanism responsible for benign neonatal sleep myoclonus.
authors.affiliation: Department of Pediatric Neurology, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan. Electronic address: yasuzuki@mch.pref.osaka.jp.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Suzuki
authors.affiliation: Department of Pediatric Neurology, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan.
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Toshikawa
authors.affiliation: Department of Pediatric Neurology, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan.
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Kimizu
authors.affiliation: Department of Pediatric Neurology, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan.
authors.forename: Sadami
authors.initials: S
authors.lastname: Kimura
authors.affiliation: Department of Pediatric Neurology, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan.
authors.forename: Tae
authors.initials: T
authors.lastname: Ikeda
authors.affiliation: Department of Pediatric Neurology, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Mogami
authors.affiliation: Department of Pediatric Neurology, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Yanagihara
mesh_terms: D000927:Anticonvulsants / Q000627:therapeutic use; D002675:Child, Preschool; D004569:Electroencephalography; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007564:Japan / Q000453:epidemiology; D008297:Male; D008881:Migraine Disorders / Q000453:epidemiology; D020447:Parasomnias / Q000188:drug therapy / Q000453:epidemiology* / Q000503:physiopathology*
chemical_list: D000927:Anticonvulsants
keywords: Benign neonatal sleep myoclonus; Cyclic vomiting syndrome; Familial; Migraine; Paroxysmal movement disorder