Norcholic acid is a bile acid and 23-carbon derivative of cholic acid .¹Levels of norcholic acid are increased in the urine of patients with liver cirrhosis or cerebrotendinous xanthomatosis (CTX), an inborn error of metabolism characterized by a deficiency in the mitochondrial enzyme sterol 27-hydrolylase (CYP27A1) that leads to progressive neurological symptoms.^2,3,4

1.Nakatomi, F., Kihira, K., Kuramoto, T., et al.Intestinal absorption and metabolism of norcholic acid in ratsJ. Pharmacobiodyn8(7)557-563(1985) 2.Bremmelgaard, A., and SjÖvall, J.Bile acid profiles in urine of patients with liver diseasesEur. J. Clin. Invest.9(5)341-348(1979) 3.Kuramoto, T., Furukawa, Y., Nishina, T., et al.Identification of short side chain bile acids in urine of patients with cerebrotendinous xanthomatosisJ. Lipid Res.101895-1902(1990) 4.Pilo de la Fuente, B., Sobrido, M.J., GirÓs, M., et al.Usefulness of cholestanol levels in the diagnosis and follow-up of patients with cerebrotendinous xanthomatosisNeurologia26(7)397-404(2011)