title: Two-tiered universal newborn screening strategy for severe combined immunodeficiency.
abstract: Outcomes for infants with severe combined immunodeficiency (SCID) would be improved by universal newborn screening, but there are not yet screening tests of sufficient accuracy for the disorder. In a pilot study, we assessed the ability of a two-tiered strategy to improve accuracy. Dried blood samples from patients were assessed with two tests for lymphopenia: interleukin-7, a T-cell growth cytokine, and TRECs, a byproduct of T-cell receptor recombination. IL-7 screening has a specificity of 96.1% and TRECs have a specificity of 92.3%. Combining these tests in a two-tiered strategy increases specificity to 100% (97-100% CI). Sensitivity was 85% for IL-7 screening and 100% for TREC screening. A two-tiered strategy may be of sufficient accuracy to enable universal SCID screening, and should be assessed in a prospective trial.
authors.affiliation: Department of Pediatrics/Immunology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA. smcghee@mednet.ucla.edu
authors.forename: Sean A
authors.initials: SA
authors.lastname: McGhee
authors.forename: E Richard
authors.initials: ER
authors.lastname: Stiehm
authors.forename: Morton
authors.initials: M
authors.lastname: Cowan
authors.forename: Paul
authors.initials: P
authors.lastname: Krogstad
authors.forename: Edward R B
authors.initials: ER
authors.lastname: McCabe
mesh_terms: D004270:DNA, Circular / Q000097:blood; D006801:Humans; D007231:Infant, Newborn; D015851:Interleukin-7 / Q000097:blood; D008231:Lymphopenia / Q000097:blood / Q000175:diagnosis; D015997:Neonatal Screening / Q000379:methods*; D010865:Pilot Projects; D012680:Sensitivity and Specificity; D016511:Severe Combined Immunodeficiency / Q000097:blood / Q000175:diagnosis*
chemical_list: D004270:DNA, Circular; D015851:Interleukin-7