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Crigler-Najjar syndrome

Disease definition

A rare hereditary disorder of bilirubin metabolism characterized by unconjugated hyperbilirubinemia due to a either a complete (type 1) or partial and inducible (type 2) hepatic deficit of UDP-glucuronosyltransferase 1A1 activity. The disorder manifests with neonatal jaundice with a risk of developing bilirubin encephalopathy.


Classification level: Disorder
  • Synonym(s):
    • Bilirubin uridinediphosphate glucuronosyltransferase deficiency
    • Bilirubin-UGT deficiency
  • Prevalence: 1-9 / 100 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Neonatal
  • ICD-10: E80.5
  • ICD-11: 5C58.00
  • OMIM: 218800  606785
  • UMLS: C5551003
  • MeSH: D003414
  • GARD: -
  • MedDRA: 10011386

Detailed information


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