Transformation of bilirubin in gastrointestinal tract and its relationship to neonatal icterus.

The object of the study was the transformation of bilirubin in the neonatal digestive tract with special reference to enterohepatic circulation of nonconjugated bilirubin and its consequences. The application of biochemical and chromatographic methods showed that bilirubin excreted by neonatal livers was qualitatively distinct from that excreted by adult livers. Already in the first meconium practically all bilirubin conjugated with glucuronic acid was hydrolyzed, which means ample availability of nonconjugated bilirubin for its reresorption by intestines.