Fetal bile acid metabolism: Analysis of urinary 3 beta-monohydroxy-Delta(5) bile acid in preterm infants

To elucidate the urinary concentration of total bile acids after birth and the profile of the usual and unusual urinary bile acids, especially 3 beta -hydroxy-5-cholen-24-oic acid (Delta (5)-3 beta -ol), we measured the conce ntrations of 13 bile acids in the urine from preterm infants vs. full-term controls by gas chromatography-mass spectrometry. The urinary concentration of total bile acids in early preterm infants below 32 weeks of gestational age significantly exceeded that of the late preterm and full-term infants (p < 0.0005). The major urinary bile acids in early preterm infants were ch olic acid, 1 beta ,3 alpha ,7 alpha ,12 alpha -tetrahydroxy-5 beta -cholan- 24-oic acid and Delta (5)-3 beta -ol. In conclusion, the high urinary conce ntrations of total bile acids in preterm infants may be due to an overprodu ction, or more likely to a low hepatic bile acid clearance. An alternative fetal pathway, the acidic pathway, may be a major route of bile acid biosyn thesis in preterm infants. Copyright (C) 2001 S. Karger AG, Basal.