Newborn screening for SCID and severe T lymphocytopenia in Europe

Abstract

Initiation of newborn screening (NBS) programs in Europe dates back to the 1960s. One of the most recent expansions of NBS programs was the addition of severe combined immunodeficiency (SCID) based on detection of T-cell receptor excision circles (TRECs). In this review, we present an overview of the current situation in Europe. To avoid a biased overview based on only published results, a 37-item survey on TRECbased NBS was sent to representatives of 46 European countries. With a response rate of 83%, we collected data of 38 countries. Seventeen of the 38 European countries that have completed the survey have nationally or regionally implemented TREC-based NBS. The survey results emphasize similarities and differences as well as common practices and challenges in TREC-based NBS. Because TRECs are a general surrogate marker for severe T lymphocytopenia, conditions other than SCID are also identified. Therefore, the initial definition of the target disease as "SCID"might need to be reconsidered and extended to "SCID and severe T lymphocytopenia."Even though complete harmonization of TREC-based NBS programs across Europe will remain challenging, collaboration and close partnerships will help in the move toward universal