Biliary Atresia

Question 1

Define biliary atresia

Answer 1

Progressive idiopathic, microinflammatory process that may involve a segment or the entire extrahepatic biliary tree

Question 2

What are the types of biliary atresia

Answer 2

Type 1: atresia of the common bile duct (10% of patients)
Type II: atresia of the hepatic ducts (2% of patients)
Type III: atresia at the porta hepatis (88% of patients).

Question 3

What are the risk factors for biliary atresia

Answer 3

Viral infection
Toxin-induced cholangiocyte injury
Defects in morphogenesis
Genetic predisposition
Defects in antenatal circulation
Immune or autoimmune dysregulation

Question 4

What are the symptoms and signs of biliary atresia

Answer 4

Jaundice (skin + sclera) >14 days/2 weeks
Pale stools (white, tan, light yellow)
Dark urine
Bruising (secondary to vit K deficiency in chronic cholestasis)
Hepatomegaly
Ascites

Question 5

What investigations should be done for biliary atresia

Answer 5

Bloods
- Serum bilirubin: conjugated >17.1
- LFTs: Disproportionately high gamma-glutamyl transferase
- Coagulation studies: Usually normal, may be elevated INR >1.5, PT >14 seconds
- FBC: Advanced disease → low platelets, low WBC

Other
- Abdominal USS: Liver usually normal texture, possibly enlarged, unlikely ductal dilation; absent or multiple spleen; ascites, triangular cord sign possible
- Hepatobiliary scintigraphy: No tracer excretion into gut after 24 hours
- Liver biopsy: (Bile duct proliferation with bile plugs)
- cholangiogram: Atresia of part or all of the biliary tree between liver and bowel
- CXR: if there is dextrocardia

Question 6

What does dextrocardia and biliary atresia suggest

Answer 6

biliary atresia splenic malformation syndrome

Question 7

What is the management for biliary atresia

Answer 7

First line: Hepatoportoenterostomy (HPE/Kasai procedure)
- 45-60 days of life
- Alleviates obstruction to prevent liver damage

+ antibiotic prophylaxis
+ Nutritional support and vitamin supplementation (vit A, alpha tocopherol, ergocalciferol, phytomenadione)
+ Consider ursodeoxycholic acid 20-30mg/kg/day orally

Second line: Liver transplantation

Question 8

What are the complications of biliary atresia

Answer 8

Growth failure
Cholangitis
Portal hypertension → oesophageal varices → GI bleed
Fat-soluble vitamin deficiency - Vit D: Bone fractures, Rickets, osteopenia, osteomalacia
Ascites (Cirrhosis)
Bile lakes/bilomas
Spontaneous bacterial peritonitis
Xanthoma (dyslipidaemia secondary to cirrhosis)
Hepatopulmonary hypertension

Question 9

What is the prognosis for biliary atresia

Answer 9

Hepatoportoenterostomy (HPE) provides transplant-free survival for at least 2 years in about half of affected children
Total bilirubin <34.2 at 3 months post-HPE - chance of being transplant-free at 2yo is 84%
70% or more of affected children will ultimately require liver transplantation