SCID, Severe Combined Immunodeficiency, is a primary immune deficiency. The defining characteristic is usually a severe defect in both the T- & B-lymphocyte systems. This usually results in the onset of one or more serious infections within the first few months of life. These infections are usually serious, and may even be life threatening, they may include pneumonia, meningitis or bloodstream infections. Children affected by SCID can also become ill from live viruses present in some vaccines. These vaccines (such as Chickenpox, Measles, Rotavirus, oral polio and BCG, etc.) contain viruses and bacteria that are weakened and don’t harm children with a healthy immune system. In patients with SCID however, these viruses and bacteria may cause severe, life-threatening infections.
“This once-fatal disease should be now seen as a pediatric emergency, a condition that needs immediate diagnosis and treatment”, says Dr. Rebecca Buckley, of Duke’s division of Pediatric Allergy and Immunology. Early diagnosis of SCID is still uncommon because not all states routinely perform a test in newborns which could alert physicians to the possibility of a T-cell defect. The newborn screening heel stick test could pick up children with SCID, as well as those with other serious immune deficiencies, that would not be apparent until the child developed an infection. This simple blood test could allow us to treat, and most likely cure SCID in an infant at a reasonable cost. If found later, less effective treatment can run into the millions. Buckley states, “What we’re saying is that essentially every baby with SCID could be cured if diagnosed early enough. SCID should be considered a pediatric emergency.”
Bubble Boy Disease
SCID is often called “bubble boy disease”. SCID became widely known during the 1970′s and 80′s, when the world learned of David Vetter, a boy with X-linked SCID, who lived for 12 years in a plastic, germ-free bubble.
There are several forms of SCID. The most common type is linked to the X-chromosome, making this form affect only males. Other forms of SCID usually follow an autosomal recessive inheritance pattern or are the result of spontaneous mutations. One of these other forms is linked to a deficiency of the enzyme adenosine deaminase (ADA) while other cases of SCID are caused by a variety of other defects.
SCID Newborn Screening Campaign:
On January 21, 2010, the Advisory Committee on Heritable Disorders in Newborns and Children voted unanimously to add screening for Severe Combined Immune Deficiency or SCID – commonly known as bubble boy disease – to the core panel for universal screening of all newborns in the United States.
On May 21, 2010 Kathleen Sebelius, Secretary of Health and Services announced the addition of Severe Combined Immunodeficiency (SCID) to the core panel of 29 genetic disorders as part of her recommendation to adopt the national Recommended Uniform Screening Panel. SCID is the first nominated condition to be added to the core panel of disorders.
SCID.net and The Immune Deficiency Foundation endorse the recommendation of the Secretary of the Department of Health and Human Services and the Advisory Committee on Heritable Disorders in Newborns and Children that every State screen newborn infants for Severe Combined Immunodeficiency Disease (SCID).
We want every state to include SCID Newborn Screening on their newborn screening panel immediately to save lives. We need the help of volunteers in every state to encourage the state governments to follow Secretary Sebelius’s recommendation. For more information and to download a Toolkit to help you work with your state please visit the IDF’s SCID Newborn Screening Campaign and the IDF Newborn Screening Blog.
States and US Territories screening all newborns for SCID are: WI, MA, NY, CA, CT, MI, CO, MS, DE, FL, TX & MN.
CDC Announces Live Rotavirus Vaccine Contraindicated for Infants with Severe Combined Immunodeficiency:
There are two makers of live rotavirus vaccines. They are GlaxoSmithKline Biologicals (Rotarix) and Merck (RotaTeq). On June 11th 2010, the CDC announced the addition of Severe Combined Immunodeficiency to the list of contraindiations for both vaccines. While the rotavirus vaccines can reduce the risk of rotavirus disease severity and even fatality in normal healthy infants, there have been several documented cases of vaccine acquired rotavirus in infants who were undiagnosed with SCID at the time the vaccine was given. The CDC recommends starting the first dose of rotavirus vaccine when an infant is 2 months old. However, without newborn screening or a family history of the disease, most SCID infants are not diagnosed until after 4 months of age and could potentially receive two doses of the vaccine before the diagnosis is made.
Before administration of rotavirus vaccines, pediatricians should: review the contraindications, review the family history for suspected immunodeficiency, and if possible check the number and percentage of lymphocytes in a Complete Blood Count (CBC) with differential, because most SCID infants present with significant lymphocytopenia for their age. Pediatricians should also follow up all infants receiving rotavirus vaccines for persistent diarrhea and should consult a clinical immunologist if necessary.
Newborn screening for SCID will provide a consistent method for pediatricans to know their patients have been screened before administering the vaccine. It is imperative that all states add SCID Newborn Screening to their core panels.