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Infantile spasms syndrome

Disease definition

A rare epilepsy syndrome characterized by onset of epileptic spasms in infants between 2 and 12 months of age, and rarely up to 24 months. Infants may have no antecedent history, or a history reflecting the underlying cause. The classical triad of epileptic spasms, hypsarrhythmia and developmental stagnation or regression is historically referred to as West syndrome.


Classification level: Disorder
  • Synonym(s):
    • West syndrome
  • Prevalence: 1-9 / 100 000
  • Inheritance: Autosomal dominant or Autosomal recessive or X-linked recessive 
  • Age of onset: Infancy, Neonatal, Childhood
  • ICD-10: G40.4
  • ICD-11: 8A62.0
  • OMIM: 300672  308350  613477  613722  615006  616139  616341  617065  617929  618298
  • UMLS: C0037769
  • MeSH: D013036
  • GARD: 7887
  • MedDRA: 10021750

Detailed information

General public



ERN produced/endorsed by ERN(s)   FSMR produced/endorsed by FSMR(s)
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