Biliary atresia is a rare disorder affecting the liver and bile ducts in infants. In this condition, the network of ducts responsible for carrying bile from the liver to the gallbladder becomes scarred and blocked. This obstruction prevents bile, a fluid that aids in fat digestion and waste removal, from draining properly. The progressive blockage can lead to significant liver damage if not addressed quickly.
Recognizing the Signs
The initial signs of biliary atresia manifest within the first two months of an infant’s life. One of the most prominent indicators is jaundice, a yellowing of the skin and eyes, that persists beyond the first two to three weeks after birth. While some jaundice is common in newborns as their liver matures, prolonged jaundice is a warning sign.
This persistent jaundice is accompanied by other distinct symptoms. Parents may notice that the baby’s stools are pale or clay-colored (acholic stools), which points to a lack of bile reaching the intestine. The infant’s urine may appear dark yellow or brown because the body is attempting to excrete excess bilirubin through the kidneys. An enlarged liver can also cause the abdomen to feel swollen or firm to the touch, and affected infants may exhibit poor weight gain due to the malabsorption of fats and nutrients.
The Diagnostic Process
When an infant presents with suggestive symptoms, tests are initiated to confirm the diagnosis. The process begins with blood tests to evaluate liver function and measure direct bilirubin in the blood. Elevated levels of direct bilirubin are an indicator that there is a blockage in the bile flow rather than a more common form of newborn jaundice.
An abdominal ultrasound is performed to visualize the liver, gallbladder, and bile ducts. This imaging test can help identify abnormalities or the absence of a normal gallbladder. To further assess bile flow, a hepatobiliary iminodiacetic acid (HIDA) scan may be ordered. During this procedure, a radioactive tracer is injected into the infant’s vein, and a special camera tracks its path to determine if bile is moving from the liver to the small intestine.
A definitive diagnosis is often made through more invasive procedures. A liver biopsy may be performed, where a small liver tissue sample is examined for signs of damage characteristic of biliary atresia. An intraoperative cholangiogram provides a conclusive answer. During surgery, a special dye is injected directly into the bile ducts to see if they are open and allow fluid to pass into the intestine, confirming the blockage.
Surgical Intervention
The primary treatment for biliary atresia is a surgical procedure known as the Kasai procedure, or hepatoportoenterostomy. This operation is not a cure but is designed to restore bile flow from the liver to the intestine. During the procedure, the surgeon removes the damaged extrahepatic bile ducts and attaches a loop of the infant’s own small intestine directly to the area of the liver where bile drains.
Timing is a factor in the success of the Kasai procedure. The surgery is most effective when performed before an infant is 8 weeks old. Early intervention increases the likelihood that bile drainage will be successfully re-established. The goal is to prevent further liver damage and allow the infant to grow more normally.
Even with a technically successful surgery, the inflammatory process that causes biliary atresia can continue to affect the intrahepatic ducts, those inside the liver. Post-operative care includes long-term antibiotics to reduce the risk of infection in the newly created bile drainage system.
Life After Surgery and Long-Term Management
Life following the Kasai procedure involves continuous medical oversight, as the surgery alleviates symptoms but does not cure the underlying condition. Ongoing care is necessary to support the child’s health and growth. Nutritional support is a component of this long-term management. Infants require special formulas containing medium-chain triglycerides, which are fats that are easier to absorb without bile.
Because the absorption of certain nutrients is impaired, children with biliary atresia must take supplements of fat-soluble vitamins.
- Vitamin A
- Vitamin D
- Vitamin E
- Vitamin K
Despite these measures, complications can still arise. One common issue is cholangitis, an infection of the bile ducts, which can occur after the Kasai procedure and requires treatment with intravenous antibiotics.
Over time, the progressive nature of the disease often leads to chronic liver problems. Many children develop cirrhosis, where the liver becomes scarred and hardened, which can lead to portal hypertension, a condition of increased pressure in the veins that carry blood through the liver. Consequently, many individuals with biliary atresia will eventually need a liver transplant, with a majority requiring one before reaching adulthood.