Biliary Atresia

Biliary atresia is a progressive fibro obliterative disease of the infant biliary tree causing obstruction of bile flow, cholestasis and rapidly progressive hepatic fibrosis.

Without restoration of biliary drainage, cirrhosis and liver failure develop early in life.

The Kasai portoenterostomy restores bile drainage in a proportion of infants and can preserve the native liver for years or decades, but it does not remove the underlying intrahepatic disease.

Early diagnosis is critical because successful native liver outcomes decline substantially with delayed surgery, particularly beyond approximately 90 days.

The infant typically appears well initially but develops persistent jaundice.

High value features are:

• Jaundice persisting beyond approximately 2 weeks
• Pale or acholic stool
• Dark urine
• Hepatomegaly
• Progressive splenomegaly
• Poor weight gain with advancing disease

Any infant with pale stool and conjugated hyperbilirubinaemia requires urgent investigation rather than reassurance for physiological neonatal jaundice.

Measure fractionated bilirubin. A direct bilirubin above approximately 1 mg/dL after 2 weeks of age is abnormal and requires evaluation.

Ultrasound: first imaging study; assess the gallbladder and porta hepatis for features supporting biliary atresia.

Liver biopsy can demonstrate obstructive cholangiopathy with ductular proliferation, bile plugs and fibrosis.

Intraoperative cholangiography: provides definitive assessment when the diagnosis remains uncertain and can be followed immediately by Kasai portoenterostomy when biliary atresia is confirmed.

Do not allow repeated nondiagnostic testing to delay referral to paediatric hepatobiliary surgery.

Kasai portoenterostomy

Perform Kasai portoenterostomy as early as possible, ideally during the first several weeks of life. Outcomes are generally better when surgery occurs before approximately 60 days, although age is a continuum rather than an absolute cutoff and potentially suitable infants presenting later should still receive specialist assessment.

The fibrotic extrahepatic biliary remnant is excised to the porta hepatis until microscopic bile ductules are exposed.

A Roux jejunal limb is then anastomosed to the porta to drain bile directly from these residual ductules.

Successful drainage is suggested by progressive reduction in conjugated bilirubin and return of pigmented stool.

Postoperative care

Nutrition is aggressive because cholestasis causes fat malabsorption and growth failure.

Use energy dense feeding with medium chain triglyceride supplementation where necessary and replace vitamins A, D, E and K according to measured deficiency and cholestasis severity.

Post Kasai ascending cholangitis is common. Fever, worsening jaundice, pale stool or inflammatory deterioration should trigger immediate IV antibiotic treatment.

Antibiotic prophylaxis for several months after Kasai is commonly used, but the optimal agent and duration remain uncertain and current evidence has not demonstrated a consistent reduction in cholangitis across all populations.

Liver transplantation

Refer early for transplant assessment when there is:

• Failed Kasai with persistent severe jaundice
• Progressive synthetic liver failure
• Recurrent severe cholangitis
• Portal hypertension with significant complications
• Refractory ascites
• Severe growth failure
• Hepatopulmonary complications
• End stage cirrhosis

An infant presenting very late with established advanced cirrhosis may be better served by primary liver transplantation rather than a low probability Kasai procedure.

Even children with successful bile drainage require lifelong hepatology surveillance because portal hypertension, cholangitis and progressive fibrosis can develop despite a functioning Kasai.