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Crigler-Najjar syndrome type 2

Disease definition

A form of Crigler Najjar syndrome (CNS), a rare hereditary disorder of bilirubin metabolism, characterized by unconjugated hyperbilirubinemia due to reduced and inducible activity of hepatic UDP-glucuronosyltransferase 1A1. The disorder clinically manifests with neonatal, isolated jaundice with a risk of developing bilirubin encephalopathy later in life due to triggers such as stress or infection.


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