Infantile spasms syndrome

What is Infantile spasms syndrome?

A rare disorder characterized by the association of clusters of axial spasms, psychomotor retardation and an hypsarrhythmic interictal EEG pattern. It is the most frequent type of epileptic encephalopathy. It may occur in otherwise healthy infants and in those with abnormal cognitive development.

Other condition names

  • Infantile spasms
  • Intellectual disability-hypsarrhythmia syndrome

Inheritance type

Autosomal dominant, Autosomal recessive, X-linked recessive


  • Europe: 1-9 in 100,000

Age of Onset

  • Childhood
  • Infancy
  • Neonatal
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