Orphanet: Megalencephaly polymicrogyria postaxial polydactyly hydrocephalus syndrome

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Megalencephaly-polymicrogyria-postaxial polydactyly-hydrocephalus syndrome

Disease definition

A rare syndrome with a central nervous system malformation as a major feature characterized by macrocephaly, megalencephaly, bilateral perisylvian polymicrogyria, variable degrees of ventriculomegaly/hydrocephalus, developmental delay and intellectual disability, oromotor dysfunction, hypotonia, seizures, and dysmorphic facial features (such as frontal bossing, low-set ears, a flat nasal bridge, and high-arched palate). Postaxial polydactyly of one or more extremities is also common.


Classification level: Disorder
  • Synonym(s):
    • MPPH syndrome
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal dominant or Not applicable 
  • Age of onset: Infancy, Neonatal
  • ICD-10: Q04.8
  • OMIM: 603387  615937  615938
  • UMLS: C1863924
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information

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Disease review articles

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