T-cell Receptor Excision Circles in Newborns with Heart Defects

Kiran A Gul,Henrik Brun,Tore G Abrahamsen,Janne Strand,Rolf D Pettersen

doi:10.1007/s00246-020-02317-y

Kiran A Gul, Henrik Brun + Show 3 more

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https://doi.org/10.1007/s00246-020-02317-y

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Journal: Pediatric Cardiology	Publication Date: Mar 13, 2020
Citations: 6	License type: open-access

Affiliation: Oslo University Hospital, University of Oslo

Abstract

In the fetus, the cardiac neural crest gives rise to both the thymus and the conotruncus of the heart. In newborn screening for severe T-cell lymphopenia neonates with congenital heart defects may be detected. In this study, we investigated the occurrence of T-cell lymphopenia in neonates with or without 22q11.2 deletion syndrome (del) suffering from heart defects. This retrospective cohort study included 125 patients with heart defects. T-cell receptor excision circles (TRECs), a measure for T-cell lymphopenia, were quantified by RT-PCR using stored newborn screening blood spots. Three patient groups were compared: non-conotruncal defects (n = 57), conotruncal defects (n = 42), and 22q11.2 del with conotruncal defects (n = 26). Significantly lower TREC values were detected in patients with 22q11.2 del and conotruncal heart defects compared to those with non-syndromic conotruncal (p < 0.001) and non-conotruncal (p < 0.001) defects. In contrast, no significant difference was found between patients with non-syndromic conotruncal and non-conotruncal heart defects (p = 0.152). Low TREC levels were obtained in neonates treated with heart surgery/intervention within 2 weeks after birth and in those with a fatal outcome (p = 0.02) independent of patient group. A correlation was found between low TREC numbers and oxygen saturation, SpO2 below 95% (p = 0.017). The SpO2 was significantly lower in the non-syndromic conotruncal group compared to non-conotruncal (p < 0.001) and 22q11.2 del group (p = 0.015). No correlation was found between low neonatal TRECs and infections needing hospitalization later in life (p = 0.135). Patients with 22q11.2 del and conotruncal defects have significantly lower TREC levels compared to patients with heart defects without this syndrome.

Highlights

T-cell lymphopenia in neonates with congenital heart defects occurring as part of a syndrome or as a non-syndromic condition, has been described in a number of studies [1, 2]
The patients were divided in three groups, those with nonconotruncal (n = 57), conotruncal (n = 42), and 22q11.2 del with conotruncal heart defects (n = 26)
In the non-syndromic patients, a slight trend of lower T-cell receptor excision circles (TRECs) values was observed in the conotruncal group compared to non-conotruncal not significant (p = 0.152)

Summary

Introduction

T-cell lymphopenia in neonates with congenital heart defects occurring as part of a syndrome or as a non-syndromic condition, has been described in a number of studies [1, 2]. Pediatric Cardiology (2020) 41:809–815 immunodeficiency (SCID) is performed routinely in the USA and other countries including Norway. In this screening, both SCID and non-SCID conditions with T-cell lymphopenia are detected when determining T-cell receptor excision circles (TRECs). After screening 3 million newborns in ten American States, Kwan et al [1] found an incidence of non-SCID T-cell lymphopenia of 1 in 14,000. Congenital syndromes associated with T-cell lymphopenia, as the 22q11.2 deletion syndrome (del) and trisomy 21 (Down syndrome) were reported in 33% of these infants

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