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Crigler-Najjar syndrome

Disease definition

Crigler-Najjar syndrome (CNS) is a hereditary disorder of bilirubin metabolism characterized by unconjugated hyperbilirubinemia due to a hepatic deficit of bilirubin glucuronosyltransferase (GT) activity. Two types have been described, CNS types 1 and 2 (see these terms). CNS1 is characterized by a complete deficit of the enzyme and is unaffected by phenobarbital induction therapy, whereas the enzymatic deficit is partial and responds to phenobarbital in CNS2.


Classification level: Disorder
  • Synonym(s):
    • Bilirubin uridinediphosphate glucuronosyltransferase deficiency
    • Bilirubin-UGT deficiency
    • Hereditary unconjugated hyperbilirubinemia
    • UGT deficiency
  • Prevalence: 1-9 / 100 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Neonatal
  • ICD-10: E80.5
  • OMIM: 218800  606785
  • UMLS: C0010324
  • MeSH: D003414
  • GARD: -
  • MedDRA: 10011386

Detailed information


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