If left untreated, patients with biliary atresia may progress to develop cirrhosis and liver failure. No cure exists for biliary atresia, but the timely diagnosis and surgical intervention improves short- and long-term outcomes in most patients. Special attention to the nutritional needs and diet are essential for children with this disorder. Special supplements, formulas, and dietary restrictions may be necessary for affected infants.

The symptoms of biliary atresia usually appear by the age of two to six weeks and include jaundice, pale stools and dark urine. Infants may present with a distended abdomen and hepatomegaly. By the age of six to ten weeks, weight gain is usually very poor, the infant is usually irritability and may show signs of portal hypertension (G.I bleeding). If left untreated, biliary atresia may result in permanent scarring of the liver.

Some children with biliary atresia may have additional congenital abnormalities including malformations of the heart (e.g., situs inversus, levocardia, and ventricular septal defects) and/or kidneys.^[1]

If untreated, the condition leads to cirrhosis, portal hypertension, liver failure but not (as one might think) to kernicterus. This is because the liver is still able to conjugate bilirubin, and conjugated bilirubin is unable to cross the blood-brain barrier. Left untreated or with failure of the Kasai procedure, biliary atresia progresses towards biliary cirrhosis, end-stage liver failure and death by age 3.

Recent large volume studies from Davenport et al. (Ann Surg, 2008) show that age of the patient is not an absolute clinical factor affecting the prognosis. In the latter study, influence of age differs according to the disease etiology—i.e., whether isolated BA, BASM (BA with splenic malformation ), or CBA (cystic biliary atresia). Performing the Kasai portoenterostomy early has very good prognosis, though some cases may ultimately need liver transplantation.^[1][2]