Follow-up of the Cohort of Newborns Screened at Birth Using TREC Analysis (DépisTrec)

Follow-up of the Cohort of Infants Screened at Birth Using TREC Analysis : DépisTrec - SUIVI

Since September 2025, neonatal screening for severe combined immunodeficiency (SCID) has been generalized in France. These genetic disorders, which are asymptomatic at birth, cause severe immunodeficiency, exposing infants to serious infections (viral, bacterial, or fungal) as early as the first year of life. Without early treatment and management, infectious complications can be life-threatening.

Studies show that this screening improves survival and quality of life and reduces treatment costs by enabling intervention before complications arise.

In France, the Ministry of Health referred this matter to the Haute Autorité de Santé (HAS), which issued a favorable opinion in January 2022 via a ministerial decree (published on April 16, 2025) regarding the combined screening for DICS and spinal muscular atrophy. These authorizations follow the DEPISTREC study (2015-2017), which demonstrated the effectiveness of this screening: 190,517 children were screened, resulting in a reduction in DICS-related deaths.

The primary objective of the study will be to describe the underlying causes of T-cell lymphopenia identified in newborns through neonatal screening by quantifying TRECs on Guthrie cards. (SCID; variant SCID; syndromic T-cell deficiency; secondary T-cell deficiency; attenuated SCID; Omenn syndrome; immunosuppressive treatment in the mother; not found; isolated prematurity).

Study Overview

• Status: Not yet recruiting
• Conditions: Severe Combined Immunodeficiencies (SCID)
• Intervention / Treatment: Other: Data collection

• Study Type: Observational
• Enrollment (Estimated): 450

Contacts and Locations

• Study Contact: Name: Caroline THOMAS; Email: marie.rimbert@chu-nantes.fr
• Study Contact Backup: Name: Marie RIMBERT; Email: marie.rimbert@chu-nantes.fr

Study Locations

• France
  • Nantes, France, 44093
    • Nantes university hospital
    • Contact: Caroline THOMAS; Phone Number: +33 0253482835; Email: caroline.thomas@chu-nantes.fr
    • Contact: Marie RIMBERT; Phone Number: +33 0253482835; Email: marie.rimbert@chu-nantes.fr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

The target population consists of all children screened for SCID in France, that is, all children born in metropolitan France and the overseas territories whose parents consent to neonatal screening of their child using the Guthrie test.

Within this population, our cohort will include all children with a positive Guthrie card screening result confirmed by lymphocyte immunophenotyping performed during the first visit with a pediatric specialist. This will include the first baby screened on or after September 1, 2025 (the start date of neonatal screening for DICS in France) and will cover a 5-year period.

Description

Inclusion Criteria:

• Children with a positive Guthrie test result, confirmed by lymphocyte immunophenotyping performed during their first visit with a pediatric specialist.

Exclusion Criteria:

• Children whose parents objected to the collection of data after receiving the informational letter

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
SCID Children; Our cohort will include all children with a positive Guthrie test result, confirmed by lymphocyte immunophenotyping performed during their first visit with a pediatric specialist. This will include the first baby screened on or after September 1, 2025 (the start date of neonatal screening for DICS in France) and will cover a 5-year period.	Other: Data collection; The categories of data processed in the study database will be: Clinical data; Laboratory data; Data related to newborn screening; Genetic data (only the results of genetic testing); Care-related data (referral center, dates of tests, etc.)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Etiology of T-cell lymphopenia identified through newborn screening using TREC quantification on Guthrie cards	Enrollment

Secondary Outcome Measures

Outcome Measure	Time Frame
Prevalence of SCID and severe T-cell lymphopenia in the screened population	Enrollment
Description of the clinical management of newborns diagnosed with T-cell lymphopenia, whether SCID or non-SCID	Enrollment
Describe the time frame for reporting test results	Enrollment

Collaborators and Investigators

• Sponsor: Nantes University Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): November 1, 2026
• Primary Completion (Estimated): August 31, 2035
• Study Completion (Estimated): August 31, 2035

Study Registration Dates

• First Submitted: July 9, 2026
• First Submitted That Met QC Criteria: July 9, 2026
• First Posted (Actual): July 15, 2026

Study Record Updates

• Last Update Posted (Actual): July 15, 2026
• Last Update Submitted That Met QC Criteria: July 9, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: neonatal screening; Severe combined immunodeficiencies (SCID); T-cell lymphopenia; Guthrie test
• Additional Relevant MeSH Terms: Primary Immunodeficiency Diseases; Genetic Diseases, Inborn; Metabolic Diseases; Immune System Diseases; Infant, Newborn, Diseases; Immunologic Deficiency Syndromes; DNA Repair-Deficiency Disorders; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Nutritional and Metabolic Diseases; Severe Combined Immunodeficiency; Health Care Quality, Access, and Evaluation; Investigative Techniques; Epidemiologic Methods; Health Care Evaluation Mechanisms; Quality of Health Care; Public Health; Environment and Public Health; Data Collection
• Other Study ID Numbers: RC26_0010

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No