biliary atresia

What Is It?
Biliary atresia is a rare but serious liver disease in infants where the bile ducts inside or outside the liver are blocked or absent. Bile is essential for digestion and carrying waste out of the liver. Without functioning bile ducts, bile builds up, causing liver damage, scarring (cirrhosis), and eventually liver failure if not treated.

Why It Matters
Biliary atresia is the most common reason for liver transplants in children. It progresses quickly, and early diagnosis and surgery, ideally before 2 months of age, greatly improve outcomes. If left untreated, it can be fatal within the first few years of life.

Key Facts (At a Glance)

  • Affects ~1 in 8,000 to 1 in 18,000 live births worldwide

  • More common in girls and in Asian and African American infants

  • Symptoms usually appear 2–8 weeks after birth

  • The Kasai procedure is the first line of surgical treatment

  • Without treatment, most infants develop end-stage liver disease by age 2

How It Affects the Body
Normally, bile flows from the liver through bile ducts into the intestines to help digest fats. In biliary atresia, these ducts are narrowed, blocked, or missing, preventing bile from exiting the liver. This causes inflammation and progressive liver damage, eventually leading to cirrhosis and liver failure.

Common Symptoms
Signs usually develop within the first 2 months of life, and include:

  • Persistent jaundice (yellowing of skin and eyes) after 2 weeks

  • Dark urine

  • Pale or clay-colored stools

  • Enlarged liver (hepatomegaly) or spleen

  • Poor weight gain or failure to thrive

  • Irritability and abdominal swelling (later signs)

Risks & Side Effects

  • Progressive liver damage and scarring

  • Portal hypertension (high blood pressure in the liver’s blood vessels)

  • Bleeding problems due to impaired clotting

  • Infections of the bile ducts (cholangitis)

  • Need for liver transplant—about 70–80% of children eventually require one even after initial surgery

  • If untreated, can lead to death within the first 2 years

Who Should Be Cautious

  • Newborns with prolonged jaundice, especially if stool is pale or urine is dark

  • Parents and healthcare providers should act quickly if signs appear; early referral to a pediatric liver specialist is critical

  • Babies born preterm or with other congenital anomalies may be at slightly higher risk, though the exact cause of biliary atresia remains unknown

When to See a Doctor
You should see a pediatrician immediately if your newborn:

  • Has jaundice that lasts beyond 2 weeks

  • Passes pale, chalky stools

  • Shows poor growth, abdominal swelling, or irritability
    Diagnosis usually includes blood tests, ultrasound, liver biopsy, and possibly a cholangiogram (dye test of the bile ducts).
    The Kasai procedure (hepatoportoenterostomy) is a surgery that connects the liver to the small intestine to drain bile. The sooner it’s performed (preferably before 60 days of age), the better the outcomes.

Related Conditions / Interactions

  • May be associated with other congenital conditions, such as:

    • Polysplenia syndrome

    • Congenital heart defects

    • Situs inversus (organs on the opposite side of the body)

  • Long-term complications:

    • Malabsorption of fat-soluble vitamins (A, D, E, K)

    • Liver cirrhosis

    • Hepatopulmonary syndrome (in advanced disease)

Last Updated: June 15, 2025