Biliary atresia and related disorders of the biliary tract, such as choledochal cysts, must be considered in the differential diagnosis of prolonged conjugated hyperbilirubinemia in the newborn (neonatal cholestasis). In this chapter, we review the current status of diagnosis and management of these disorders, as well as advances in the intriguing quest for an understanding of their pathogenesis.

OVERVIEW

Neonatal hepatobiliary diseases, including biliary atresia, choledochal cysts, and “idiopathic” neonatal hepatitis, have historically been viewed as a continuum – a gradation of manifestations of a basic underlying disease process in which giant cell transformation of hepatocytes is strongly associated with inflammation at any level of the hepatobiliary tract. These disease entities may be polar end points of a common initial insult, as originally stated in the unifying hypothesis of Landing [1]. The end result represents the sequela of the inflammatory process at the primary site of injury. Landing suggested that this inflammatory process may injure bile duct epithelial cells, leading to either duct obliteration (biliary atresia) or weakening of the bile duct wall with subsequent dilatation (choledochal cyst). The lesions may be dependent on the stage of fetal development when the injury occurs and the site within the developing hepatobiliary tree at which the injury occurs [1, 2]. A relationship of the pathogenesis of these obstructive cholangiopathies of infancy to the process of development is suggested by the association with disorders of situs determination such as the polysplenia syndrome and the observation of the so-called ductal plate malformation within the liver of a few patients with biliary atresia.