biliary atresia

Introduction

Classifiaction:

• type 1:
  • obliteration of the common bile duct
  • proximal bile ducts are patent
• type 2:
  • atresia of the hepatic duct, with cystic structures found in the porta hepatis
• type 3: (>90% of patients)
  • atresia of the right & left hepatic ducts to the level of the porta hepatis

Epidemiology

• 1 per 10,000-15,000 live births
• most common surgically treatable cause of cholestasis encountered during the newborn period
• highest in Asian populations, black:white ratio 2:1

Pathology

• obliteration or discontinuity of the extrahepatic biliary system, resulting in obstruction to bile flow

Laboratory

• serum bilirubin (total and direct):
  • conjugated hyperbilirubinemia
• hepatobiliary function tests
  • serum alkaline phosphatase
  • serum 5' nucleotidase
  • serum gamma-glutamyl transpeptidase
  • serum ALT, serum AST
  • serum bile acids
• serum alpha1-antitrypsin with Pi typing:
  • alpha1-antitrypsin deficiency is the most common inherited liver disease that presents with neonatal cholestasis
• sweat chloride:
  • biliary tract involvement is a well-recognized complication of cystic fibrosis

Diagnostic procedures

• cholangiography

Complications

• biliary cirrhosis, hepatocellular carcinoma

Differential diagnosis

• intrahepatic biliary hypoplasia
• Alagille syndrome
• hemochromatosis
• Caroli disease
• Herpes simplex
• cholestasis
• lipid storage disorders
• cystic fibrosis
• rubella
• cytomegalovirus
• syphilis
• galactosemia
• toxoplasmosis

Management

• surgical correction

More general terms

• atresia (atretic, atresic, imperforate)
• biliary disease