Etiology of biliary cirrhosis: diagnostic features and a new classification.

The current classification of biliary cirrhosis, in which only a "primary" and a "secondary" form are recognized, has lost its usefulness for diagnosis, patient management, and research. In this article, a new terminology and a new etiologic classification of biliary cirrhosis and its underlying conditions are proposed, based on the current understanding of small-duct and large-duct biliary diseases and their causes.