Details

Autor(en) / Beteiligte

• Baker, Mei W., MD
• Grossman, William J., MD, PhD
• Laessig, Ronald H., PhD
• Hoffman, Gary L., BS
• Brokopp, Charles D., DrPH
• Kurtycz, Daniel F., MD
• Cogley, Michael F., BS
• Litsheim, Thomas J., BS
• Katcher, Murray L., MD, PhD
• Routes, John M., MD

Titel

Development of a routine newborn screening protocol for severe combined immunodeficiency

Ist Teil von

• Journal of allergy and clinical immunology, 2009-09, Vol.124 (3), p.522-527

Ort / Verlag

New York, NY: Mosby, Inc

Erscheinungsjahr

2009

Quelle

MEDLINE

Beschreibungen/Notizen

• Background Severe combined immunodeficiency (SCID) is characterized by the absence of functional T cells and B cells. Without early diagnosis and treatment, infants with SCID die from severe infections within the first year of life. Objective To determined the feasibility of detecting SCID in newborns by quantitating T-cell receptor excision circles (TRECs) from dried blood spots (DBSs) on newborn screening (NBS) cards. Methods DNA was extracted from DBSs on deidentified NBS cards, and real-time quantitative PCR (RT-qPCR) was used to determine the number of TRECs. Positive controls consisted of DBS from a 1-week-old T− B− NK+ patient with SCID and whole blood specimens selectively depleted of naive T cells. Results The mean and median numbers of TRECs from 5766 deidentified DBSs were 827 and 708, respectively, per 3.2-mm punch (∼3 μL whole blood). Ten samples failed to amplify TRECs on initial analysis; all but 1 demonstrated normal TRECs and β-actin amplification on retesting. No TRECs were detected in either the SCID or naive T-cell–depleted samples, despite the presence of normal levels of β-actin. Conclusions The use of RT-qPCR to quantitate TRECs from DNA extracted from newborn DBSs is a highly sensitive and specific screening test for SCID. This assay is currently being used in Wisconsin for routine screening infants for SCID.