Immunodeficiency awareness & severe combined immunodeficiency newborn screening
Figure 1. David Vetter, “the bubble boy” at Texas Children’s Hospital
April is Immunodeficiency Awareness Month where we acknowledge the remarkable advances in the identification and treatment of severe combined immunodeficiency (SCID). SCID is a primary immunodeficiency and is a pediatric emergency. It is a condition that needs immediate diagnosis and treatment otherwise it is fatal. In SCID, T cells essential to the immune system’s ability to fight infections, are absent. SCID babies have no signs of any illness at birth but are at high risk of death within in the first year of life. The treatment, that offers cure, is transplantation of stem cells from healthy donors.
SCID became known as "the bubble boy disease" during the 1970s-80s from the experience of David Vetter who had SCID and was a patient of Dr. William T. Shearer and the Immunology team at Texas Children’s Hospital before the disease itself and treatment options were well understood. (Figures 1. & 2.) David was identified because of the loss of his older sibling to SCID. David lived for 12 years in a plastic bubble at Texas Children’s to protect him from life-threatening germs until bone marrow transplantation was possible. It was not until a decade after David’s transplant and death that the first gene for SCID was discovered. Many other SCID genes have since been discovered and all have poor or absent T cells. David taught the world about SCID, its genetics and the impact of transplantation.
Today, we celebrate a new way of identifying SCID in babies right from birth through the SCID newborn screen that tests for the baby’s T cells in the form of T-cell Receptor Excision Circles (TRECs) through the newborn heel-stick blood sample on the Guthrie Card. (Figure 3., A & B) In 2008, a nationwide campaign for SCID screening started in Wisconsin and now most states across the nation, including Texas, have adopted screening for SCID via the Guthrie Card tests. However, this still leaves some states without screening for SCID. A number are in the pilot stage and do plan for SCID screening to begin, but there are two states, Indiana and Louisiana, that remain without SCID screening or planning. (Figure 4.) The SCID Newborn Screening confirms the frequency of SCID is approximately 1 out of every 40,000 live births. In Texas, this means at least a dozen babies each year are identified with SCID who may have otherwise been missed. Within weeks of life, before the chance for lethal infection, these babies can receive life-saving bone marrow transplants. The allergy and immunology team at Texas Children's has the expertise and resources for timely confirmation of the SCID diagnosis and works jointly with the bone marrow transplantation team to prepare all babies with SCID and their families for a cure.
References and Resources Allergy & Immunology Service, Texas Children's Hospital Journal of Allergy and Clinical Immunology, March 2017 Cover The Immunodeficiency Foundation, www.primaryimmune.org @IDFcommunity The Jeffrey Model Foundation, @info4PI SCID Newborn Screen, SCID.net The Newborn Screen, savebabies.org Figure 1. David Vetter, “the bubble boy” at Texas Children’s Hospital Figure 2. Dr. William T. Shearer and David at Texas Children’s Hospital Figure 3. A. Newborn Screen heel-stick blood sample placed onto the Guthrie Card. B. T-cell Receptor Excision Circles (TRECs) analysis, abnormal result requires timely confirmatory test with an immunologist Figure 4. SCID Newborn Screen map, United States, from the March 2017 Cover of the Journal of Allergy and Clinical Immunology
Everyone! Come to The Annual David's Dream Run on Saturday, April 29 at: Woodforest National Bank Stadium 1911 David Memorial Drive Shenandoah, Texas 77385 On-site registration time: 7:30 a.m. Race start time: 8 a.m. Preregistration: click here This event honors the memory of David, “the Bubble Boy,” and is sponsored by the children, parents and staff of David Elementary School in The Woodlands. All funds raised as a result of David’s Dream are donated to the David Center in the Immunology, Allergy & Rheumatology Section of Texas Children's Hospital to advance care and research for patients with SCID and immunodeficiencies. Open to everyone!