What is Severe Combined Immune Deficiency (SCID)

Severe combined immunodeficiency (SCID) is an inherited immune system disease, known as a “primary immunodeficiency.”

Children inherit this disease from their parents. SCID's multiple genetic mutations cause multiple defects in the immune system.

The body's immune system takes care of fighting infections and anything it sees as foreign invaders to the body.

In SCID disease — the most severe primary immunodeficiency — the body has little to no immune response.

Because of this, children with this disease have a high risk of getting infections that become severe.

Bacteria, viruses, fungus, and other germs that are not harmful to children with normal immunity can be fatal to children with SCID.

Doctors see this disease in very young children.

When babies are born, their systems have protective immunity from antibodies they received while in the womb. As these antibodies from the mother leave the system over the first few months, the symptoms of SCID begin.

How Common is SCID?

Severe combined immunodeficiency is extremely rare. It occurs in about one in 100,000 births.

It may be more common (but still rare) in some Native Americans and people of Turkish descent.

SCID Symptoms

Symptoms of SCID are much like those of other childhood illnesses. But, SCID symptoms may last longer and become severe faster than symptoms of other diseases.

Symptoms may include:

  • Sinus, lung, and other respiratory infections that keep coming back.
  • Ear infections.
  • Overgrowth of yeast in the mouth (thrush) or severe diaper rash.
  • Skin infections that don't respond well to treatment.
  • Diarrhea.
  • Slow growth or weight gain.

Complications of severe combined immunodeficiency

Children with primary immune deficiencies like SCID are more prone to infections than others are. Their bodies may not clear these infections at all when treated.

Infections that wouldn't have much effect on other children can quickly become life-threatening in kids with SCID.

Children with this condition may need to be physically isolated to protect them from germs.

Diagnosing SCID

Most states now screen newborns for this disorder, because although it is rare, it's vital to treat it early.

Doctors diagnose SCID by a blood test that measures lymphocytes — a type of white blood cell.

More blood tests can show what type of SCID disease is present, and which immune cells aren't working properly.

Severe Combined Immune Deficiency Treatment

The goal of SCID treatment is to prevent your child from getting infections, which can become life-threatening.

Enzyme-replacement therapy can treat some types of SCID, but not all kinds. This treatment doesn't cure SCID.

The most accepted treatment that cures SCID is bone marrow transplant. Many children need to have a bone marrow transplant before the age of three months.

The Hillman Center for Pediatric Transplant pioneered a reduced-intensity bone marrow transplant program. The program helps reduce the negative effects a bone marrow or stem cell transplant has on the body's organs.

Paul Szabolcs, MD

Chief, Bone Marrow Transplantation and Cellular Therapies

Dr. Szabolcs is a pioneer in reduced-toxicity/intensity unrelated donor cord blood transplant for inborn immunity errors. He's the first to show promise in sequential lung and bone marrow transplantation from the same unrelated deceased donor.

What to Expect

If your child has been diagnosed with SCID, we want you to know that you are not alone – the Center for Rare Disease Therapy is here to help. Here’s what you can expect when you come to us for a consultation.

How quickly can we get an appointment?

At the Center for Rare Disease Therapy, a doctor specializing in disorders of immunity can usually see a new patient within 1 to 2 weeks. To make an appointment, please call Jodie Vento at 412-692-7273 or send an email to rarecare@chp.edu.

How long should we expect our first visit with the doctor to take?

You can expect your first visit to take from 4 to 6 hours. Your child will receive a complete evaluation and may be seen by several doctors and other health care professionals.

What will happen during our first visit?

Your child will receive a complete evaluation to establish or confirm a precise diagnosis and determine how much the disease has affected the child. Because we work as a team here at the Center for Rare Disease Therapy, during your visit, your child may be seen by several doctors and other health care professionals. These other health care professionals may include a neurologist, a heart specialist, a surgeon, a nutritionist, a genetic counselor, a psychologist, and a specialist in child development.

We understand that the whole family is affected when a child has a rare disease. We see each family as our partner in caring for their child. We think the best approach to caring for a child with a rare disease emerges when we combine our depth of experience in rare diseases with your expertise in what’s best for your child.

We will talk with you about what we think is likely to happen with your child in the near future and about options we can suggest for treating and caring for your child. If surgery is an option for your child, we will help you understand what the surgery entails and what you may need to do to prepare for it. We will also talk with you about what you can do at home to care for your child and improve his or her quality of life. Please feel free to ask our specialists any questions you have about your child’s disease, treating and caring for your child, or anything else that is on your mind.

By the end of your visit, you will have a care plan tailored to your child’s needs and an appointment for a follow-up visit in 3 months. You will be introduced to our clinical nurse practitioner, who is available by phone or video conference to help you with any concerns you have between now and your next appointment.

How long might we have to wait for test results?

Depending upon the types of tests that the doctors order, you can expect to receive a phone call within 2 weeks to explain test results and discuss recommended next steps. Test results are also made available on Children's patient portal, myCHP, which is provided at no cost to patients, parents, and guardians.

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Contact Us

At the Center for Rare Disease Therapy, every child diagnosed with a rare disease receives an individualized treatment plan and family-centered care.

For an appointment, consultation, or patient referral with an expert at Children’s Hospital of Pittsburgh of UPMC for a child diagnosed with SCID, please contact:

Jodie Vento, MGC, LCGC
Phone: 412-692-7273
Email: RareCare@chp.edu

Clinical Studies

*Immunodeficiency and End-Stage Lung Disease Treatment with BOLT+BMT Procedure

Bilateral Orthotopic Lung Transplant (BOLT) in Tandem With CD3+ and CD19+ Cell Depleted Bone Marrow Transplant (BMT) From Partially HLA-Matched Cadaveric Donors

Read more

*Non-Malignant Marrow Disorder Treatment using Reduced Intensity Conditioning – Phase II

Study of Reduced-Intensity Conditioning In Patients With Non-Malignant Disorders Undergoing Umbilical Cord, Bone Marrow, or Peripheral Blood Stem Cell Transplantation

Read more

*Original research initiated by investigators at UPMC Children’s Hospital of Pittsburgh.