TREC, KREC as potential predictors for infection development in preterm infants: a single-center study

Populational screening with TREC/KREC determination is a universal method for detecting severe combined immunodeficiency prior to the onset of infectious diseases. The prognostic significance of TREC/KREC low levels in preterm infants with secondary lymphopenia has not been sufficiently studied as yet. The purpose of this research was to determine the value of TREC/KREC indicators for predicting severe infections in preterm infants. Materials and methods used: the study was conducted on the basis of the Stavropol Krai Regional Clinical Perinatal Center (Stavropol, Stavropol Krai, Russia). An analysis of neonatal screening results for 100 preterm infants was conducted in Jan. 01, 2023-June 30, 2024, and clinical and laboratory data of 18 patients who were hospitalized in the ICU were studied retrospectively. Statistical analysis utilized the Mann-Whitney non-parametric test and ROC curve analysis. Results: among the causes of secondary lymphopenia not associated with congenital immune defects, preterm birth accounts for 77.8%. Preterm infants have reduced levels of TREC and KREC with statistically significant differences observed in those with gestational ages below 28 weeks. The median TREC in preterm infants admitted to the ICU was significantly lower than in the comparison group. A TREC value below 509 copies/105 may be used as a predictor for life-threatening infections. Conclusion: preterm infants with low and abnormal TREC/KREC values are at high risk for adverse outcomes and therefore require throughout and careful monitoring.