Specific diseases Biliary atresia		Biliary atresia (BA) is a progressive inflammatory disorder of the extrahepatic biliary tree of unknown etiology. First recognized in 1817, it is the most common identified cause of direct jaundice in newborns. It was not until 1959 that definitive surgical therapy for BA, the Kasai portoenterostomy, was described. In 1982, an NIH Consensus Conference declared liver transplant as an acceptable treatment for end-stage liver failure due to BA. BA is currently the most common indication for liver transplantation in childhood, accounting for 40-50% of all pediatric liver transplants. BA has 2 different clinical presentations - the embryonic and the postnatal form. The latter accounts for 80-90% of cases. They share the clinical symptoms of jaundice, acholic stools and hepatomegaly, but differ in timing of the onset of jaundice, the presence of associated anomalies and clinical outcome. Clinically, infants with BA present with jaundice between 3 and 8 weeks of age. They usually appear well initially with an adequate weight gain. The stools soon become acholic, although they may have some color early. There is a variable degree of splenomegaly, besides the hepatomegaly. There is no family history of cholestasis. Liver enzymes are mildly to moderately elevated; GGTP is always increased. Absence of the gallbladder on ultrasound is highly suggestive of BA, but its presence does not rule it out. Another highly predictive sign is a "triangular cord" in the hilum, which corresponds to the fibrous cone of tissue at the bifurcation of the portal vein. This sign, along with an absent or clearly abnormal gallbladder, has a 100% positive predictive value for BA. It is reported to be 88% predictive even when the gallbladder is normal. Nuclear medicine scintiscans, especially after 5 days of phenobarbital, potentially can differentiate BA from intrahepatic disorders. However, there is much overlap and a low positive predictive value. Diagnosis ordinarily depends on liver biopsy, initially percutaneous. When typical pathologic findings of BA are seen, exploratory laparotomy with operative cholangiogram is the next step. The cholangiogram will not only demonstrate the extent of biliary obstruction, but also the anatomic variants of the extrahepatic biliary tree. Therapy of BA is primarily surgical. Prior to development of the portoenterostomy, mortality from BA was close to 100%. In this operation, the biliary tree is dissected back to the porta hepatis where it is transected; Roux-en-Y anastomosis is then made from the hilum of the liver to the proximal jejunum, using a 35-40 cm jejunal limb. Most patients have improved biliary flow with decreasing bilirubins after portoenterostomy. Survival with native liver is 30-60% at 5 years and 25-50% at 10 years. Known factors leading to better outcome are younger age at surgery and size of biliary remnants. Indications for liver transplant include persistent cholestasis associated with severe malnutrition, growth failure and hepatocellular dysfunction; decompensated cirrhosis with intractable ascites, portal hypertension and bleeding esophageal varices; and recurrent cholangitis. Return to top of page