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Congenital bile acid synthesis defect type 2

Disease definition

Congenital bile acid synthesis defect type 2 (BAS defect type 2) is an anomaly of bile acid synthesis (see this term) characterized by severe and rapidly progressive cholestatic liver disease, and malabsorption of fat and fat-soluble vitamins.


  • Synonym(s):
    • BASD2
    • Cholestasis with delta(4)-3-oxosteroid 5-beta-reductase deficiency
  • Prevalence: Unknown
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Neonatal
  • ICD-10: K76.8
  • OMIM: 235555
  • UMLS: C1856127
  • MeSH: C535443
  • GARD: 10045
  • MedDRA: -

Detailed information


Additional information

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