title: Short-lasting unilateral neuralgiform headache attacks with ispilateral facial flushing is a new variant of paroxysmal extreme pain disorder.
abstract: BACKGROUND
  We encountered a 5-year-old girl who had short-lasting, severe, unilateral temporal headaches with ipsilateral lacrimation, nasal congestion and rhinorrhoea, and facial flushing after severe attacks. Family history revealed similar short-lasting, severe headaches in an older brother, younger sister, mother, maternal aunt, and maternal grandfather's brother.
  
  
  METHODS
  We performed routine laboratory examinations and electrophysiological and radiological studies for three children, and whole-exome sequencing to determine the genetic causality in this family.
  
  
  RESULTS
  Focal hyperperfusion of the right trigeminal root entry zone was seen during a right-sided attack in one child, while left-sided temporal headache attacks were provoked by bilateral electrical stimulation of the upper extremities in another. We identified a novel SCN9A mutation (NM_002977: c.5218G>C, p.Val1740Leu) in all affected family members, but not in any of the unaffected members. SCN9A encodes the voltage-gated sodium-channel type IX alpha subunit known as Na(v)1.7.
  
  
  CONCLUSIONS
  Gain-of-function mutations in Na(v)1.7 are well known to cause paroxysmal extreme pain disorder (PEPD), a painful Na-channelopathy characterized by attacks of excruciating deep burning pain in the rectal, ocular, or jaw areas. The SCN9A mutation suggests that our patients had a phenotype of PEPD with a predominant symptom of short-lasting, severe, unilateral headache.
authors.affiliation: Department of Neurology, Japanese Red Cross Shizuoka Hospital, 8-2 Ohtemachi, Aoi-ku, Shizuoka, Shizuoka, 420-0853, Japan, neurologyimai@gmail.com.
authors.forename: Noboru
authors.initials: N
authors.lastname: Imai
authors.forename: Noriko
authors.initials: N
authors.lastname: Miyake
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Saito
authors.forename: Emiko
authors.initials: E
authors.lastname: Kobayashi
authors.forename: Masako
authors.initials: M
authors.lastname: Ikawa
authors.forename: Shinya
authors.initials: S
authors.lastname: Manaka
authors.forename: Masaaki
authors.initials: M
authors.lastname: Shiina
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Ogata
authors.forename: Naomichi
authors.initials: N
authors.lastname: Matsumoto
mesh_terms: D002675:Child, Preschool; D003027:Cluster Headache / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology; D004252:DNA Mutational Analysis; D005260:Female; D005483:Flushing / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology; D006261:Headache; D006801:Humans; D009154:Mutation; D062556:NAV1.7 Voltage-Gated Sodium Channel / Q000235:genetics; D010146:Pain / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology; D012007:Rectum / Q000002:abnormalities* / Q000503:physiopathology
chemical_list: D062556:NAV1.7 Voltage-Gated Sodium Channel; C486866:SCN9A protein, human