Increased Mortality Rate in Infants with Abnormal T-Cell Receptor Excision Circles

Abstract Purpose: T-Cell Receptor Excision Circles based newborn screening (TREC-NBS) allows for early detection and improved disease outcome in infants with primary immunodeficiency disorders (PIDD). The utility of abnormal TREC-NBS in infants without PIDD is not well studied. To determine the value of abnormal TREC-NBS in predicting mortality and morbidity in infants without PIDD. Methods: 365,207 newborn screens in the database from October 2011 to December 2014 were reviewed. 467 newborns had an abnormal TREC-NBS either during the initial or repeat screen. 1,390 newborns with normal TREC-NBS served as matched controls based on gestational age, birth weight, neonatal intensive care unit status (NICU), and race. Any infant with a PIDD diagnosis was excluded. Demographic data was obtained through NBS, birth certificates, and death certificates records from Michigan Department of Health and Human Services (MDHHS) databases. Results: Overall, infants with positive TREC-NBS had higher mortality (14.6% versus 3.3% in controls) even when PIDD is ruled-out. Transient positive TREC-NBS was not associated with higher mortality, but unresolved or late TREC-NBS was associated with higher mortality. More Black infants had positive TREC-NBS than infants of other races. Children with positive TREC-NBS were more likely to have NICU stays and have low Apgar scores. Infants with unresolved or late TREC-NBS were more likely to have congenital anomalies. Conclusion: Infants with positive TREC-NBS may be at a higher risk of morbidity and mortality and should be carefully followed, especially if discharged home before a repeat screen can be completed.