What Is Byler Disease?

Byler disease is an inherited condition caused by a faulty gene.

In children with Byler disease, cells in the liver can’t release bile — a fluid that helps the body digest food. As a result, bile builds up in the liver, causing symptoms such as jaundice, itching, impaired growth, and delayed puberty.

Byler disease is one of a group of diseases known as progressive familial intrahepatic cholestasis.

  • Progressive: it gets worse over time.
  • Familial: it runs in families.
  • Intrahepatic: it occurs inside the liver.
  • Cholestasis: poor bile flow.

Children are often around 3 months old when diagnosed with Byler disease.

Your Child’s Byler Disease Consult and Care: What to Expect

If your child has Byler disease, we want you to know you’re not alone. The Center for Rare Disease Therapy (CRDT) at UPMC Children's Hospital of Pittsburgh is here to help.

To make an appointment for your child or refer a patient for Byler disease care, contact us by:

Here’s what you can expect when you come to us for a consult.

How can we get an appointment for my child’s Byler disease?

We’ll schedule an appointment with one of our children’s liver doctors within a reasonable time based on your child’s condition.

We’ll need a copy of your child's medical records before your first visit.

Looking over your child's records helps us:

  • Decide how soon we should see your child at the center.
  • Avoid doing tests that your child has already had.
  • Arrange visits with other specialists as needed.

What should I expect at my child’s first visit to the CDRT?

Your first visit will take about 3 to 4 hours.

Your child will receive a complete assessment to confirm or make a precise Byler disease diagnosis. We’ll also check to see how much the disease has affected your child.

Since we work as a team, other doctors might see your child on the first or on follow-up visits.

These may include a:

  • Hearing expert.
  • Surgeon.
  • Nutritionist.
  • Genetic counselor.

Before the end of your visit, we will:

  • Talk with you about what to expect with your child’s health in the near future.
  • Give you details on Byler disease treatment options. If surgery is an option, we’ll make sure you know what to expect and how to prepare.
  • Suggest ways you can care for your child at home to improve their quality of life.
  • Provide a care plan tailored to your child’s needs.
  • Make an appointment for a follow-up visit in 3 months.

You’ll also meet our clinical nurse practitioner who will be your point of contact between now and your next appointment. You can contact them by phone or video conference about any concerns you have.

Before you leave, please ask us any questions you have about your child’s Byler disease diagnosis or treatment.

How long will I have to wait for my child’s Byler disease test results?

It depends on the types of tests your child had during your visit.

In most cases, we’ll call you within 2 weeks to explain test results and discuss recommended next steps.

You can also access your child’s test results on Children's patient portal, MyCHP. It’s free for our patients, parents, and guardians.

Partners in Your Child’s Byler Disease Care

When a child has a rare health problem like Byler’s disease, it affects the whole family.

At the Center for Rare Disease Therapy, we see each family member as our partner in caring for their child.

The best care plans happen when we combine our rare disease knowledge with your expertise in your child’s needs.


Center for Rare Disease Therapy patient storiesMeet Our Rare Disease Center Patients

Learn how others are finding help and hope for their child’s rare disease through the expertise at UPMC Children’s.

View Center for Rare Disease Therapy patient stories »


Contact Us About Your Child’s Byler Disease

At the CRDT, every child diagnosed with a rare disease receives a tailored treatment plan and family-centered care.

For an appointment, consult, or referral, contact us:

We’ll be in touch within 2 business days.