Biliary atresia - GM

Question 1

what is biliary atresia

Answer 1

a rare congenital condition affecting the biliary tree
progressive inflammation and fibrosis of the extrahepatic ducts leading to cholestasis, liver damage and failure

Question 2

biliary atresia usually presents in

Answer 2

infants and young children
may be life-threatening if left untreated

Question 3

aetiology of biliary atresia

Answer 3

mostly unknown: likely multifactorial genetic and environmental factors

Question 4

biliary atresia may involve

Answer 4

• the common bile duct
• the common bile duct and also the hepatic duct
• atresia of almost all extrahepatic ducts, including porta hepatis

Question 5

biliary atresia may also involve

Answer 5

other congenital abnormalities

Question 6

when do symptoms develop

Answer 6

symptoms of biliary atresia may not present until after the first week of life, at which point features of cholestasis develop

Question 7

what symptoms would there be

Answer 7

typically, infants present with persistent neonatal jaundice (beyond 14 days)
the jaundice is usually associated with pale stools and dark urine due to biliary obstruction

Question 8

clinical examination

Answer 8

the most common finding on clinical examination is jaundice
in late stages, clinical findings may also include
- hepatosplenomegaly, ascites, failure to thrive due to malabsorption of fats

Question 9

differential diagnosis

Answer 9

choledochal cyst
cholelithiasis
spontaneous perforation of the bile duct
Allagile syndrome: a rare disorder where a baby is born with fewer bile ducts than normal

differentials not related to the gall bladder may include:
- cystic fibrosis
- lipid storage disorders
- idiopathic neonatal hepatitis
- congenital infections
- alpha-1-antitrypsin deficiency

Question 10

relevant lab investigations

Answer 10

newborn bloodspot screening will exclude cystic fibrosis
liver function tests: conjugated hyperbilirubinaemia and raised gamma-glutamyltransferase (GGT)

Question 11

first line imaging

Answer 11

ultrasound

Question 12

key features on ultrasound

Answer 12

the triangular cord sign
hepatic artery changes, which will mainly larger
gallbladder ghost triad: small, atretic gallbladder, irregular or lobular contour, lack of smooth echogenic mucosal lining

Question 13

nuclear medicine

Answer 13

hepatobiliary scintigraphy or hepatobiliary iminodiacetic acid HIDA scan

in biliary atresia, there will be good hepatic uptake of radioisotope, but no biliary excretion of the radioisotope into the bowels after 24 hours

Question 14

management

Answer 14

surgery should be performed by 45 days of life to avoid liver transplantation

Question 15

surgical intervention of choice

Answer 15

Kasai portoenterostomy
removes damaged bile ducts and replaces them with a loop of intestine to allow the bile to flow from the liver to the intestine
this procedure is not always curative

Question 16

liver transplantation

Answer 16

liver transplantation is sometimes required
sometimes this may be required even after a succesful Kasai procedure due to the progession of liver damage

Question 17

indication for liver transplant

Answer 17

failure of Kasai procedure
growth retardation
development of portal hypertension and its complications (variceal bleeding, ascites)
progressive liver dysfunction marked by pruritus and coagulopathy

Question 18

what prophylaxis do these children require

Answer 18

all patients require antibiotic prophylaxis for the first year of life to prevent the development of cholangitis

Question 19

complications of surgical intervention

Answer 19

ascending cholangitis
obstruction
cirrhosis - which may lead to hepatocellular carcinoma
portal hypertension