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Classic maple syrup urine disease

Disease definition

Classic maple syrup urine disease (classic MSUD) is the most severe and probably common form of MSUD (see this term) characterized by a maple syrup odor in the cerumen at birth, poor feeding, lethargy and focal dystonia, followed by progressive encephalopathy and central respiratory failure if untreated.


Classification level: Subtype of disorder
  • Synonym(s):
    • Classic BCKD deficiency
    • Classic MSUD
    • Classic branched-chain alpha-ketoacid dehydrogenase deficiency
    • Classic branched-chain ketoaciduria
  • Prevalence: 1-9 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Neonatal
  • ICD-10: E71.0
  • OMIM: 248600
  • UMLS: C0268568
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information

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