Orphanet: Ocular anomalies axonal neuropathy developmental delay syndrome

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Ocular anomalies-axonal neuropathy-developmental delay syndrome

Disease definition

A rare mitochondrial disease characterized by signs and symptoms within a phenotypic and metabolic spectrum that includes global developmental delay, hypotonia, intellectual disability, optic atrophy, axonal neuropathy, hypertrophic cardiomyopathy, lactic acidosis, and increased excretion of Krebs cycle intermediates. Other variable features are spasticity, seizures, ataxia, congenital cataract, and dysmorphic facial features. Age of onset is in the neonatal period or infancy.


Classification level: Disorder
  • Synonym(s):
    • Harel-Yoon syndrome
  • Prevalence: <1 / 1 000 000
  • Inheritance: -
  • Age of onset: Neonatal, Infancy
  • ICD-10: E88.8
  • OMIM: 617183
  • UMLS: -
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information

Genetic Testing

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