Urinary excretion of tetrahydroxylated bile acids in children with alpha 1-antitrypsin deficiency and neonatal cholestasis.

Urinary excretion of bile acids was investigated in seven infants with alpha 1-antitrypsin deficiency and neonatal cholestasis. The infants were followed prospectively and the bile acid analysis was repeated after 2-8 years in four of the patients. Bile acid excretion during 24 h was quantified by gas-liquid chromatography and the bile acids were identified by gas-liquid chromatography-mass spectrometry. In contrast to healthy controls, all the patients excreted tetrahydroxylated bile acids during cholestasis and in the postcholestatic period. The patients who developed cirrhosis during the observation period had lower concentration of tetrahydroxylated bile acids than those with a more favourable course. Our findings suggest that tetrahydroxylation of bile acids might be an alternative pathway for elimination of bile acids in cholestasis of infancy, and that those infants exhibiting a good capacity of polyhydroxylation might have a better prognosis.