Biliary atresia
Biliary atresia is progressive obliteration of the extrahepatic bile ducts causing neonatal cholestasis; persistent jaundice with pale stools or dark urine needs prompt split bilirubin testing and urgent specialist referral because early surgery offers the best chance of preserving the native liver.
Definition
Biliary atresia is a neonatal cholangiopathy with progressive inflammation, fibrosis and obliteration of the extrahepatic bile ducts. The resulting obstruction causes conjugated cholestasis and, without effective bile drainage and specialist care, progressive liver disease.
First principles
Conjugated bilirubin identifies cholestasis
The liver conjugates bilirubin and normally excretes it in bile. When bile flow is obstructed, conjugated bilirubin accumulates in blood and is excreted in urine, producing dark urine; reduced bile pigment reaching the gut produces pale or acholic stools. A neonate with prolonged jaundice therefore needs total and conjugated bilirubin measured rather than being labelled with physiological or breast-milk jaundice.
This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.

