Newborn screening for T-cell deficiency

Purpose of review Newborn screening for T-cell deficiency is ongoing in two states, and the published results of 1 year of screening in Wisconsin are favorable. In this review, the history, methodology, results, challenges, and future direction of screening are discussed. Recent findings As a concept, newborn blood screening (NBS) has evolved from the detection of elevated levels of phenylalanine on filter paper to the application of DNA-based technologies to identify T-cell lymphopenia in infants with severe combined immunodeficiency (SCID). After diagnosis by NBS, one infant with SCID received a hematopoietic stem cell transplant (HSCT), and several others are currently undergoing evaluation for HSCT. The utility of NBS for T-cell deficiency is dependent on the NBS program to define a rigorous screening protocol, ensure seamless follow-up of all identified infants, and demand a renewed emphasis on the training of future clinical immunologists to care for these patients. DNA-based NBS assays are currently being evaluated to identify infants with other serious diseases. Summary Newborn screening for T-cell deficiency has ushered in a new era in the detection of infants with primary immunodeficiencies.