Case report: paucity of interlobular bile ducts in Chinese children.

Sixteen Chinese children with cholestasis since early infancy were diagnosed to have paucity of interlobular bile ducts (PILBD) or its equivalent. Twelve children belonged to the syndromic group of PILBD and four children belonged to the non-syndromic group. A definite histological diagnosis of bile duct paucity was established in only two children (aged 4 and 9 months) during the first percutaneous needle biopsy. In the remaining 14 children a varying degree of bile duct destruction was evident in the follow up percutaneous or wedge liver biopsies. The evolving changes were characterized by inflammatory infiltration near or at the ductal wall, the presence of dysmorphic ductules, the degeneration of ductal epithelia and a progressive decrease of interlobular bile ducts. Of 10 children who underwent laparotomy for definite diagnosis, kasai operation was performed in two of them. In the syndromic PILBD group, all children, including two paired siblings, had at least three of five major clinical features. Hypoplasia of the extrahepatic biliary tree was found in five children and atresia of the extrahepatic bile duct was found in one. Three of six children studied were shown, by polymerase chain reaction, to have cytomegalovirus infection in the liver. This study demonstrates that bile duct paucity is a result of progressive bile duct destruction. A definitive diagnosis is difficult to make in early infancy. Thus, the careful evaluation of extrahepatic features in cholestatic children and follow-up liver biopsies are indicated. Although the pathogenetic mechanism of PILBD is unknown, bile duct destruction is the common pathway leading to paucity of bile ducts irrespective of syndromic or non-syndromic types.