ICD-11

Anomalies of bile acid synthesis are a group of sterol metabolism disorders due to enzyme deficiencies of bile acid synthesis in infants, children and adults, with variable manifestations that include cholestasis, neurological disease, and fat malabsorption. Eight inborn errors have been clearly identified, 7 of which lead to liver cholestasis and include: 3β-hydroxy-C27-steroid oxidoreductase deficiency (type 1), Δ4-3-oxosteroid 5β-reductase deficiency (type 2), oxysterol 7α-hydroxylase deficiency (type 3), 2-methylacyl-CoA racemase deficiency (type 4), bile acid CoA ligase deficiency, and cerebrotendinous xanthomatosis. Cholesterol 7α-hydroxylase deficiency leads to hypercholesterolaemia without liver cholestasis.