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Crigler-Najjar syndrome type 2

Disease definition

A hereditary disorder of bilirubin metabolism characterized by unconjugated hyperbilirubinemia due to reduced and inducible activity of hepatic bilirubin glucuronosyltransferase (GT). Crigler-Najjar syndrome type 2 (CNS2) is a milder form of Crigler-Najjar syndrome (CNS) than Crigler-Najjar syndrome type 1 (CNS1).


Classification level: Subtype of disorder
  • Synonym(s):
    • Arias syndrome
    • Bilirubin uridinediphosphate glucuronosyltransferase deficiency type 2
    • Bilirubin-UGT deficiency type 2
    • Hereditary unconjugated hyperbilirubinemia type 2
    • UGT deficiency type 2
  • Prevalence: Unknown
  • Inheritance: Autosomal recessive 
  • Age of onset: Childhood
  • ICD-10: E80.5
  • OMIM: 606785
  • UMLS: C0268311  C2931132
  • MeSH: C536213
  • GARD: 8683
  • MedDRA: 10011387
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