Biliary Atresia
Blocked or missing bile ducts in a newborn's liver
Quick Facts
- Type: Newborn liver and bile duct disorder
- Key sign: Jaundice persisting past 2 weeks, pale stools
- Main treatment: Kasai surgery, sometimes liver transplant
- Timing: Early diagnosis and surgery are critical
Overview
Biliary atresia is a rare but serious condition that affects newborns. The bile ducts, the small tubes that carry bile from the liver to the intestine, become blocked, scarred, or are missing. Bile is needed to digest fats and to remove certain waste products. When it cannot drain, it backs up in the liver, causing inflammation, scarring, and progressive liver damage.
The condition usually becomes apparent in the first weeks of life, often as jaundice that does not go away like ordinary newborn jaundice. Biliary atresia is one of the most important causes of persistent jaundice in infants and a leading reason for liver transplantation in children. Early diagnosis and surgery greatly improve the outlook, so prompt evaluation of prolonged newborn jaundice is essential.
Symptoms
Babies with biliary atresia often appear healthy at birth, with symptoms developing over the first few weeks:
- Jaundice that persists beyond about two weeks of age or appears after the newborn period
- Pale, clay-colored, or white stools, because bile is not reaching the intestine
- Dark urine
- A swollen abdomen and an enlarged liver
- Poor weight gain over time
The combination of persistent jaundice with pale stools and dark urine is an important warning sign that needs urgent evaluation, as it points to a problem with bile drainage rather than ordinary newborn jaundice.
Causes
The exact cause of biliary atresia is not known. It is not inherited in a simple way and is not caused by anything the parents did during pregnancy. Several possibilities are being studied:
- Abnormal development: the bile ducts may not form properly before birth in some babies.
- Inflammation and immune response: in many cases the ducts appear to be damaged by inflammation after birth, possibly triggered by a viral infection or an abnormal immune reaction.
Whatever the trigger, the result is progressive blockage and scarring of the bile ducts, leading to bile buildup and liver injury that worsens without treatment.
Risk Factors
- Being a newborn (the condition appears in early infancy)
- Being female, as it is slightly more common in girls
- Certain associated birth differences in some affected babies, such as problems with the spleen or heart
In most cases, no specific risk factor is identified, and the condition occurs in otherwise healthy newborns.
Diagnosis
Because early surgery is so important, prompt and thorough evaluation of persistent jaundice is key.
- Blood tests: measuring bilirubin (including the conjugated, or direct, fraction) and liver function; a raised conjugated bilirubin is a red flag.
- Ultrasound: imaging of the liver and bile ducts to look for abnormalities.
- Specialized scans: tests to assess whether bile is draining from the liver.
- Liver biopsy: a small tissue sample can show changes typical of biliary atresia.
- Surgical exploration (cholangiogram): sometimes needed to confirm the diagnosis and treat it during the same operation.
Treatment
Treatment is surgical, and timing matters greatly.
- Kasai procedure: the main initial surgery, in which the blocked ducts are removed and a loop of intestine is connected to the liver to allow bile to drain. It works best when done early, generally in the first weeks to couple of months of life.
- Nutritional support: special formulas and vitamin supplements, because poor bile flow affects the absorption of fats and certain vitamins.
- Liver transplant: needed for many children, either when the Kasai procedure does not provide lasting drainage or when liver damage progresses.
Even after a successful Kasai operation, ongoing specialist care is needed to monitor liver health and growth.
Prevention
Biliary atresia cannot be prevented because its cause is unknown and it is not related to anything done during pregnancy. The most important step is early detection so treatment can begin quickly:
- Have any jaundice that lasts beyond about two weeks of age evaluated promptly
- Watch for pale, clay-colored stools and dark urine and report them to your doctor
- Keep newborn check-up appointments so jaundice and growth can be monitored
When to See a Doctor
Seek medical evaluation promptly for a newborn or infant who has:
- Jaundice that lasts longer than about two weeks
- Pale, clay-colored, or white stools
- Dark urine
- A swollen abdomen or poor weight gain
These can be signs of biliary atresia or another bile drainage problem. Because the success of surgery depends heavily on early treatment, do not wait to have persistent newborn jaundice checked. Seek emergency care if the baby develops fever, lethargy, or signs of serious illness.
Frequently Asked Questions
How is biliary atresia different from normal newborn jaundice?
Ordinary newborn jaundice is common and usually fades within a couple of weeks. Biliary atresia causes jaundice that persists, often with pale stools and dark urine, and reflects blocked bile drainage and liver injury. Persistent jaundice should always be evaluated.
Why is early surgery so important?
The Kasai procedure works best when performed early, generally within the first weeks to couple of months of life, before extensive liver scarring develops. Delayed treatment lowers the chance of successful bile drainage and increases the likelihood of needing a liver transplant.
Does the Kasai procedure cure biliary atresia?
It can restore bile drainage and slow liver damage, and some children do well for years afterward, but it is not always a permanent cure. Many children eventually need a liver transplant, and all require ongoing specialist care.
What causes biliary atresia?
The exact cause is unknown. It may involve abnormal development of the bile ducts before birth or inflammation and immune-related damage after birth, possibly linked to a viral trigger. It is not caused by anything the parents did during pregnancy.
What are the warning signs parents should watch for?
The main warning signs are jaundice lasting beyond about two weeks, pale or clay-colored stools, and dark urine. Reporting these promptly allows for quick testing and timely treatment.
References
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Biliary Atresia.
- MedlinePlus, U.S. National Library of Medicine. Biliary atresia.
- American Liver Foundation. Biliary atresia.
- Children's Hospital resources, National Institutes of Health (NIH).