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Atypical Rett syndrome

Disease definition

A rare genetic neurological disorder characterized by the presence of two or more of the main criteria for classic Rett syndrome (loss of acquired purposeful hand skills, loss of acquired spoken language, gait abnormalities, stereotypic hand movements), a period of regression followed by recovery or stabilization, and five out of eleven supportive criteria (breathing difficulties, bruxism, impaired sleep pattern, abnormal muscle tone, peripheral vasomotor disturbances, scoliosis/kyphosis, delayed growth, small cold hands and feet, inappropriate laughter or screaming spells, decreased pain sensation, and intense eye communication). Like classic Rett syndrome, it almost exclusively affects girls, while the disease course may be either milder or more severe.


Classification level: Disorder
  • Synonym(s):
    • Atypical RTT
    • Rett syndrome variant
  • Prevalence: -
  • Inheritance: Autosomal dominant or X-linked dominant 
  • Age of onset: Neonatal
  • ICD-10: F84.2
  • ICD-11: LD90.Y
  • OMIM: 300672  312750  613454  617903  617904
  • UMLS: C2748910
  • MeSH: C567576
  • GARD: 4694
  • MedDRA: -

Detailed information


Disease review articles


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