Among the leading causes of newborn cholestasis, and the foremost reason for cirrhosis and liver related death in children.
Biliary atresia (BA) is an idiopathic, fibro-obliterative disease of the intra- and extrahepatic biliary tree.
BA presents in the neonatal period, and is a progressive disease that can rapidly culminate in biliary cirrhosis and premature death, if untreated.
The incidence of BA varies geographically.
It is the most common cause of conjugated hyperbilirubinemia in infants and neonates and is the leading indication for liver transplantation among children.
Its pathogenesis has been attributed to viral infection, immune dysregulation, genetic predisposition, exposure to environmental toxins,and abnormalities in morphogenesis.
It may occur in isolation or with other congenital malformations.
Most patients with BA are born full-term with normal birth weights.
It is the most frequent indication for liver transplant in the pediatric population.
It is a result of an idiopathic, rapidly progressive, obliterating fibrosclerosing injury to large bile ducts during the first months of life.
An inheritable disease.
Occurs in 1:15,000 to 1: 20,000 live births in north America, with the highest incidence rates in Asia 1:6000-1:9000, in French Polynesia 1:3000.
It manifest during the first weeks of life with jaundice and pale stools in an otherwise healthy infant.
Patients may be asymptomatic until 2 to 6 weeks of age, at which point they develop onset of jaundice, acholic stools, and hepatomegaly.
Characteristic laboratory abnormalities include elevations in total and direct bilirubin, aminotransferases, and GGT >200 IU/L.
Abdominal ultrasound excludes other causes of extrahepatic biliary obstruction such as choledochal cyst, choledocholithiasis, or sludge.
Histology include bile ductular proliferation, plugs of bile within bile ducts, portal tract edema, and fibrosis.
Evidence of biliary obstruction on cholangiography confirms the diagnosis.
A hepaticoportoenterostomy restores bile flow from the liver to the proximal small intestine.
The Kasai procedure restores bile flow from the liver to the small intestine by creating an anastomosis between a Roux-en-Y loop of jejunum and the hilum of the liver.
The rapidity of diagnosis and completion of the hepaticoportoenterostomy determines outcome:
technical success was achieved among 80% of patients within the first 60 days of life, but this decreased to approximately 20% when the operation was delayed at 120 days of life.
Even with successful restoration of bile flow, progressive liver disease develops and necessitates eventual liver transplantation in more than 80% patients with BA.
10-year survival rates after liver transplantation are high at 86%.
Approximately 2/3 of newborns experience benign, self resolving physiological jaundice due to unconjugated hyperbilinemia.
Biliary atresia results in obstructive jaundice with conjugated direct hyperbilirubinemia.
Left untreated, infants with biliary atresia die by age 3.
The Kasai procedure is most effective in the early weeks of life.
Most successful outcomes are achieved when surgeries performed at 60 days or younger, with the most with the best outcomes achieved at age 30 days or younger.