Abnormal distribution of nerve fibers in the liver of biliary atresia.

We investigated changes in the pattern of hepatic innervation in liver specimens from 15 infants with biliary atresia and 4 age-matched controls by immunohistochemical methods. In the control, nerve fibers identified by immunoreactivity for neural cell adhesion molecule (NCAM) and S100 protein were present around the branches of hepatic arteries, portal veins and bile ducts in the portal areas and the hepatic lobules. In biliary atresia, NCAM and S100 positive nerve fibers were increased in the vicinity of the hepatic arteries and the portal veins in the enlarged portal areas, while no nerve fibers were observed around bile ducts and periportal ductules which became NCAM positive. No innervation in the lobules was seen in any cases regardless of the histological alteration. These findings may suggest that the abnormal innervation in the liver with biliary atresia does not occur as a result of structural changes in liver architecture caused by portal fibrosis and inflammation, but is associated with immaturity or malformation of hepatic innervation in the patients.