Related Experiment Video
Updated: Jan 30, 2026
How to Obtain Reliable Visual Event-related Potentials in Newborns
Published on: October 24, 2019
Newborn Screening for Severe Combined Immunodeficiency and T-cell Lymphopenia in California, 2010-2017
George S Amatuni1,2, Robert J Currier1, Joseph A Church3
1Department of Pediatrics, University of California, San Francisco and Benioff Children's Hospital, San Francisco, California.
Insights
California
Area of Science:
- Immunology
- Genetics
- Pediatrics
Background:
- Newborn screening for severe combined immunodeficiency (SCID) is crucial for early detection and treatment.
- California implemented SCID screening in 2010 using T-cell receptor excision circles (TRECs).
Purpose of the Study:
- To evaluate the performance and outcomes of California's SCID newborn screening program over 6.5 years.
- To assess the effectiveness of TREC-based screening for identifying SCID and other T-cell lymphopenias.
Main Methods:
- Reviewed demographic data, TREC and flow-cytometry results, and clinical follow-up for infants screened.
- Analyzed diagnoses, treatments, and outcomes for infants with abnormal screening results.
Main Results:
- Identified SCID at a rate of 1 in 65,000 births, with 94% survival due to prompt treatment.
- Detected non-SCID T-cell lymphopenias, including DiGeorge syndrome, and noted 2 cases of delayed-onset SCID missed by initial screening.
Conclusions:
- TREC-based newborn screening is highly sensitive and specific for SCID and T-cell lymphopenia, supporting widespread adoption.
- The California program demonstrates the effectiveness of population-based screening for improving infant outcomes.
Objectives:
Newborn screening for severe combined immunodeficiency (SCID) was instituted in California in 2010. In the ensuing 6.5 years, 3 252 156 infants in the state had DNA from dried blood spots assayed for T-cell receptor excision circles (TRECs). Abnormal TREC results were followed-up with liquid blood testing for T-cell abnormalities. We report the performance of the SCID screening program and the outcomes of infants who were identified.
Methods:
Data that were reviewed and analyzed included demographics, nursery summaries, TREC and lymphocyte flow-cytometry values, and available follow-up, including clinical and genetic diagnoses, treatments, and outcomes.
Results:
Infants with clinically significant T-cell lymphopenia (TCL) were successfully identified at a rate of 1 in 15 300 births. Of these, 50 cases of SCID, or 1 in 65 000 births (95% confidence interval 1 in 51 000-1 in 90 000) were found. Prompt treatment led to 94% survival. Infants with non-SCID TCL were also identified, diagnosed and managed, including 4 with complete DiGeorge syndrome who received thymus transplants. Although no cases of typical SCID are known to have been missed, 2 infants with delayed-onset leaky SCID had normal neonatal TREC screens but came to clinical attention at 7 and 23 months of age.
Conclusions:
Population-based TREC testing, although unable to detect immune defects in which T cells are present at birth, is effective for identifying SCID and clinically important TCL with high sensitivity and specificity. The experience in California supports the rapid, widespread adoption of SCID newborn screening.
Related Concept Videos
01:25Immunodeficiency Diseases
There are three main causes of immunodeficiency...
01:21Impedance Combination
01:18Combination Of Resistors
01:16Combining Functions
02:46Genetic Screens
Forward genetic screens
Forward or “classical” genetic screens involve creating random mutations in an organism’s DNA using radiation, mutagens, or insertion of additional bases, which...
01:23Stresses under Combined Loadings
The process begins by slicing the tube at critical points and analyzing the internal forces and stress components at these sections, focusing on the centroid. Normal stresses, generated by axial forces and bending moments, are either compressive or tensile and vary across the section from...