Time course of the intrahepatic lesion of extrahepatic biliary atresia: a morphometric study.

The time course of the intrahepatic lesions of untreated extrahepatic biliary atresia was evaluated by morphometric analysis of 49 specimens from 27 patients. The data show an early phase of rapid bile ductular proliferation, with peak in this material at 205 days, followed by rapid duct regression to approximately 400 days, and slower progressive intrahepatic duct loss thereafter. The ratio of ducts to connective tissue in portal tracts follows a similar course. Connective tissue in portal tracts rises on a slower course and continues to increase after maximum duct regression is reached, so the ratio of parenchyma to fibrous septa falls over the later course of the process. Although duct and connective tissue proliferation in hepatic portal tracts is associated in many liver diseases, the data of this study demonstrate dissociability of the relationships, with the fibrosis in the later stages of the intrahepatic process in extrahepatic biliary atresia apparently neither responsive to nor inducing biliary ductular proliferation.