Maldevelopment as a Possible Etiologic Factor in Biliary Atresia

Introduction

Extrahepatic biliary atresia (EHBA) is a progressive fibrosis of the extrahepatic biliary tree, causing obstructive jaundice in neonates. It is a devastating disease that leads to cirrhosis and the need for liver transplantation in the majority of children. Despite improvements in the surgical management of EHBA since the condition was first described, little is known about the pathogenesis of the disease. Gross and microscopic observations show that the typical pathogenetic manifestations in EHBA are most prominent at the porta hepatis. The classical description is of an inflammatory and fibrosing process that involves the entire biliary tract [1].

We report the case of an infant with EHBA in whom the excised portal tract and hilar tissue at the time of Kasai's procedure showed an unusual finding of hyaline cartilage portoenterostomy on histopathological examination. We present the third such case to be reported in the literature and discuss the possibility of defective embryonic development or aberrant metaplasia of the mesenchyme at the porta hepatis as etiologic factors in the pathogenesis of EHBA.

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