Biliary Atresia

Epidemiology and Etiology:

· Progressive necroinflammatory process

· Most common indication for liver transplant in children

· Idiopathic

· Not likely genetic

·

· Perinatal form (most common)

· Presents at 4-8wks

· Embryonic or fetal form (10-35%)

· Cholestatic as newborns

· Congenital anomalies associated (ex. polysplenia syndrome / left isomerism)

Common sites:

· Extrahepatic biliary tree

· Intrahepatic biliary system is involved over time

Gross features:

· Loss of patency of the lumen

· Involving a segment or all of the extrahepatic biliary tree

Histologic features:

· Gautier and Eliot description of resected biliary remnant:

· Type 1 – absent lumen replaced by a fibrous cord

· Type 2 – multiple small lumina, usually < 50um, arrayed around a fibro-inflammatory cord

· Type 3 – central lumen, sometimes containing bile, corresponding to an altered bile duct

· Extensive degenerative changes and injury to the epithelium usually observed

· Inflammation and fibrosis of the wall

· Liver:

· Expansion of the portal spaces

· Proliferation of bile ducts and ductules containing bile plugs

· Distinguishes from Alagille syndrome (JAG-1 mutations)

· Edema and fibrosis of portal tracts

· Portal inflammatory infiltration

· Hematopoiesis variable

· Ballooning and giant cell transformation of hepatocytes

· Progressive loss of intrahepatic bile ducts

Immunophenotype:

Marker:

Sensitivity:

Specificity:

Molecular features:

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Other features:

· Uniformly fatal in the first 2 years of life

· Malignancy may be associated

· Hepatocellular carcinoma

· Hepatoblastoma

· cholangiocarcinoma

References:

· Russo P, Ruchelli ED, Piccoli DA. Pathology of Pediatric Gastrointestinal and Liver Disease. 1st ed. Springer; 2004.