RESULTS: Screening programmes in several federal states in the United States have been supplemented with the T-cell receptor excision circle assay during the past few years to identify children with SCID. The reported experience indicates that an efficient and validated screening approach for SCID is feasible on a population-based scale.
CONCLUSIONS: In the light of recent advances, severe PID ought to be discussed for their rapid implementation in national NBS programmes based upon clinical, social and economical criteria as consolidated in the extended 22-item Wilson-Jungner framework. Although SCID currently most favourably fulfils these screening guidelines, other strong candidates can be identified among primary immunodeficiency disorders. Future efforts of healthcare professionals and policy makers are essential to improve the concept of neonatal screening for PID.