Biology of the neonate

Fetal bile acid metabolism: analysis of urinary 3beta-monohydroxy-delta(5) bile acid in preterm infants.

PMID 11474144


To elucidate the urinary concentration of total bile acids after birth and the profile of the usual and unusual urinary bile acids, especially 3beta-hydroxy-5-cholen-24-oic acid (Delta(5)-3beta-ol), we measured the concentrations 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 cholic acid, 1beta,3alpha,7alpha,12alpha-tetrahydroxy-5beta-cholan-24-oic acid and Delta(5)-3beta-ol. In conclusion, the high urinary concentrations of total bile acids in preterm infants may be due to an overproduction, 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 biosynthesis in preterm infants.