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Maple syrup urine disease

Disease definition

A rare inherited disorder of branched-chain amino acid metabolism classically characterized by poor feeding, lethargy, vomiting and a maple syrup odor in the cerumen (and later in urine) noted soon after birth, followed by progressive encephalopathy and central respiratory failure if untreated. The four overlapping phenotypic subtypes are: classic, intermediate, intermittent and thiamine-responsive MSUD.


Classification level: Disorder
  • Synonym(s):
    • BCKD deficiency
    • BCKDH deficiency
    • Branched-chain 2-ketoacid dehydrogenase deficiency
    • Branched-chain ketoaciduria
    • MSUD
  • Prevalence: 1-9 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Neonatal, Childhood
  • ICD-10: E71.0
  • ICD-11: 5C50.D0
  • OMIM: 248600  615135
  • UMLS: C0024776
  • MeSH: D008375
  • GARD: 3228
  • MedDRA: 10026817

Detailed information

General public


Disease review articles

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