title: Atypical morphologic presentation of biliary atresia and value of serial liver biopsies.
abstract: BACKGROUND
  Liver biopsy findings are important in diagnosing extrahepatic biliary atresia. Diffuse ductular proliferation is a characteristic finding. We describe four patients with conjugated hyperbilirubinemia in whom the initial liver biopsy findings showed a lack of ductular proliferation, despite subsequent development of biliary atresia.
  
  
  RESULTS
  On initial biopsy, paucity of intrahepatic bile ducts was present in three of four patients, with a bile duct to portal space ratio of 0.3 to 0.4 (normal, 0.9-1.8). A normal bile duct to portal space ratio of 1.0 was observed in the fourth patient. Ductular proliferation became apparent in three subjects between 9 and 12 weeks of age, and biliary atresia was noted at the time of a Kasai portoenterostomy. The fourth child had well-developed biliary cirrhosis at liver transplantation.
  
  
  CONCLUSIONS
  Changes characteristic of biliary atresia may appear even after 9 weeks of age. Bile duct paucity and normal bile duct to portal space ratio do not preclude the subsequent development of biliary atresia. Infants with unexplained conjugated hyperbilirubinemia and acholic stools should undergo sequential liver biopsies until clinical improvement occurs or until biliary atresia can be excluded from the differential diagnosis.
authors.affiliation: Department of Pathology, North Shore University Hospital, New York University School of Medicine, Manhasset, New York 11030, USA.
authors.forename: Georgia
authors.initials: G
authors.lastname: Azar
authors.forename: Debra
authors.initials: D
authors.lastname: Beneck
authors.forename: Bernard
authors.initials: B
authors.lastname: Lane
authors.forename: James
authors.initials: J
authors.lastname: Markowitz
authors.forename: Fredric
authors.initials: F
authors.lastname: Daum
authors.forename: Ellen
authors.initials: E
authors.lastname: Kahn
mesh_terms: D001649:Bile Duct Diseases / Q000175:diagnosis / Q000473:pathology; D001653:Bile Ducts, Intrahepatic / Q000002:abnormalities*; D001656:Biliary Atresia / Q000175:diagnosis / Q000473:pathology*; D001706:Biopsy; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D006932:Hyperbilirubinemia / Q000209:etiology; D007223:Infant; D007231:Infant, Newborn; D008099:Liver / Q000473:pathology*; D008297:Male