What Are Urea Cycle Disorders?

Inborn Error of Protein Metabolism

Urea cycle disorders (UCDs) are a group of inherited conditions caused by faulty genes.

Children with UCDs develop high levels of ammonia, a toxic substance, in their bodies. Ammonia is a byproduct of protein digestion.

Normally, enzymes in the liver help the body convert ammonia to urea — a harmless substance excreted in urine. This process is the “urea cycle.”

In children with UCDs, one of these enzymes is missing or defective. As a result, the ammonia stays in the body, causing brain damage and other serious problems.

Jerry Vockley, MD, PhD

Chief of Genetic and Genomic Medicine

Dr. Vockley is a global leader in inborn errors of metabolism treatment and research. He’s also a founder of the North American Metabolic Academy.

Your Child's Urea Cycle Disorder Consult and Care: What to Expect

If a doctor diagnosed your child with a UCD, we want you to know you’re not alone. The Center for Rare Disease Therapy (CRDT) at UPMC Children’s Hospital of Pittsburgh can help.

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

Here’s what you can expect when you come to us for your child’s first UCD consult.

What should I expect at my child’s first visit for UCD care?

You can expect your first visit to take from four to six hours. Your child will receive a complete assessment from one of the center's doctors.

The doctor will make or confirm a UCD diagnosis and find out how much the disease has progressed.

Because we work as a team at the center, other doctors and staff might see your child during your visit.

These may include a:

  • Neurologist.
  • Heart specialist.
  • Surgeon.
  • Nutritionist.
  • Genetic counselor.
  • Psychologist.
  • Child development specialist.

What are the next steps after my child's UCD visit to the Center for Rare Disease Therapy?

Members of your child's care team will talk with you about:

  • Likely next steps for your child.
  • UCD treatment options.
  • Ways to help your child's quality of life at home.

By the end of your visit, you'll have a UCD care plan tailored to your child's needs. We'll also schedule a follow-up visit.

You'll meet our nurse practitioner. You can contact them by phone or video conference with any concerns before your next visit.

Before you leave, please ask us about your child's UCD, treatment, or anything else on your mind.

How long will I need to wait for my child's UCD test results?

We'll call within two weeks to review the test results and the next steps for your child's UCD care.

You can also find your child's test results if you have a MyCHP account — Children's patient portal.

MyCHP lets you manage your child's health online. It's free for kids getting treatment at UPMC Children's Hospital of Pittsburgh and their loved ones.

Partners in Your Child's Urea Cycle Disorder Care

A child with a rare disease like a UCD affects the whole family. We see each family member as our partner at the CRDT.

The best care happens when we merge our UCD expertise with your knowledge of your child's needs.

Center for Rare Disease Therapy patient storiesMeet Our CRDT Patients

Learn how families are finding help and hope from the rare disease experts at UPMC Children’s Hospital of Pittsburgh.

View Center for Rare Disease Therapy patient stories »

Contact Us About Your Child’s UCD

At the CRDT, we provide each child diagnosed with a rare disease with tailored treatment and family-centered care.

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

We’ll be in touch within two business days.