Neonatal Screening for SCID: The French Experience

Abstract

After it was demonstrated in 2005 that T cell receptor excision circle (TREC) quantification for dried blood spot (DBS) samples on Guthrie cards is an effective means of SCID screening and following several pilot studies, the practice was formally recommended in the US in 2010. More and more countries have adopted it since then. In France, before the health authorities could recommend adding SCID to the list of five diseases that were routinely screened for, feasibility and cost-effectiveness studies had to be conducted with a sufficiently large cohort of neonates. We carried out three such studies: The first sought to verify the effectiveness of the assay. The second, DEPISTREC, evaluated the feasibility of universal SCID screening in France and assessed the clinical benefit and economic advantage it would provide. Through the third study, NeoSKID, still under way and to continue until recommendations are issued, we have been offering SCID screening in the Pays de la Loire region of France. This review briefly describes routine newborn screening (NBS) and management of primary immunodeficiency diseases (PIDs) in France, and then considers the lessons from our studies and the status of SCID screening implementation within the country.

Newborn Screening for SCID: The very first prospective pilot study from Turkey

“…Thus, total recall rate for examination by a pediatric immunologist and immune workup via ow cytometry was 0.049%. This rate was close to 0.04% reported in 72.411 samples by the French study DEPISTREC that totally 190,517 newborns screened prospectively [11]. Among our 10 babies, two newborns were identi ed to have 0 copies for TREC.…”

“…Cost calculations are reported as 4.25 dollars in the USA, 4.21 Euro in France; worldwide 4-5 dollars per test is reported in general [10,11]. In our study, the cost of TREC measurement and SCID screening was calculated as 5.1 dollars/test which refers about to 45 TL (Turkish Lira).…”

“…including Turkey, pilot programs or regional screening efforts are reported to be in place [10]. The incidence of SCID reported to be 1 out of 63.500 live births in France [11] In the USA, screening program data was published for 23 states reporting the incidence of SCID as 1:58.000 [2]. As a result of national screenings in Israel and Norway, SCID incidences were the same and were reported as 1:22.500 [4,12].…”

Current Status of Newborn Bloodspot Screening Worldwide 2024: A Comprehensive Review of Recent Activities (2020–2023)

“…As a prerequisite for addition to the French NBS panel, feasibility and cost-effectiveness studies must be completed along with assay validation. Studies supporting the addition of SCID include performance of the TREC assay for SCID [ 786 ], a review of the evidence supporting SCID screening in France [ 787 ], and the status of screening implementation, including lessons learned [ 788 ]. Recent studies supporting the addition of other conditions also exist: a systematic review of NBS test accuracy for TYR-I using succinylacetone [ 789 ]; a world view of practices and pitfalls in defining an algorithm for primary carnitine deficiency screening [ 790 ]; and a review of costs and quality of life of patients with SMA [ 791 ].…”

A large-volume sputum dry storage and transportation device for molecular and culture-based diagnosis of tuberculosis

“…DBS cards have been widely used for collection, preservation, transportation, and downstream molecular and immunological testing. [3][4][5] Since their advent, several technological advances have been made in the DBS card technology, addressing issues such as variability in hematocrit levels, 6 enabling the separation of plasma from whole blood, 7,8 and increasing the accuracy of volumetric sampling. 9,10 However, there continues to be a lack of large volume dry storage devices.…”