Severe Combined Immune Deficiency

Also known as: SCID, severe combined immunodeficiency, “boy in the bubble” syndrome.

What is severe combined immune deficiency?

Severe combined immune deficiency is a rare dangerous genetic birth defect that essentially doesn’t allow your child’s body to develop an immune system with which to fight any type of infection. Children with this disease lack function in both their T- and B-lymphocyte cells, which are both critical parts of the immune system.

What causes severe combined immune deficiency?

There are a number of different types of SCID most of which are caused by mutations in a child’s genes that are present at birth. Some forms of SCID can run in families.

What are the symptoms of severe combined immune deficiency?

Many infants/children may not be diagnosed or have any symptoms until they encounter an infection. The lack of function of immune system T-lymphocytes and B-lymphocytes leaves children susceptible to very serious, dangerous and potentially life-threatening bacterial, viral, parasitic and fungal infections.

However, some children may only present failure to grow properly.

What are severe combined immunodeficiency care options?

Prevention of potential infections by isolation from other children, strict hand hygiene regimens, family and friends wearing protective masks, vaccination of siblings (SCID children should not receive vaccinations) is extremely important for children with severe combined immune deficiency, as is giving appropriate antibiotic or drugs to fight infections, antibody infusions, and stem cell/bone marrow transplantation.


Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: April 14, 2022 10:58 AM

Pediatric Allergy & Immunology

The Clinical Immunology Division evaluates recurrent infections, and suspected or confirmed immunodeficiency disorders. Our Miami location also evaluates HIV and fevers of unknown origin.

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