Establishing reference intervals for high-sensitivity cardiac troponin T in neonates and infants

Objectives High-sensitivity cardiac troponin T (hs-cTnT) is used in pediatric healthcare to diagnose and assess the prognosis of various cardiac diseases, such as acute myocarditis, congenital heart disease, dilated cardiomyopathy, and heart failure. However, the standardized age-related reference intervals, 99th percentile cut-offs, and clinical guidelines are currently unavailable, especially in newborns and infants, making interpreting this biomarker challenging. Methods Residual serum samples were collected from 1,047 pediatric subjects with no cardiovascular disease, including 145 neonates and 902 infants. The concentrations of hs-cTnT were analyzed using Roche’s Elecsys Troponin T hs assay. The age-related 99th percentile cut-offs with 90 % confidence intervals (CIs) of hs-cTnT were established. Results Subjects were divided into age subgroups as follows: newborns (0–30 days, n=142), infants aged 1 month (31–60 days, n=223), 2 months (61–90 days, n=152), 3–4 months (91–150 days, n=211), 5–6 months (151–210 days, n=149), and 7 months-1 year (211–365 days, n=149). Serum hs-cTnT concentrations were highest during the first month of life and progressively declined in a year. The 99th percentile cut-offs of hs-cTnT concentration in each group were as follows: 114 (90 % CI: 114-114), 65.6 (63.7–66.1), 55.2 (54.4–55.2), 30.4 (29.1–30.9), 23.5 (22.1–23.5), 12.7 (12.4–12.7) ng/L. The 97.5th percentile cut-offs for each group were 109.4 (105.2–114), 62.5 (60.5–63.9), 52.3 (50.3–54.4), 29 (28.5–29.1), 20.5 (19.2–23.4), and 12 (12–12.1) ng/L. Conclusions This study aimed to provide reliable pediatric reference values for hs-cTnT based on a population of well-child children. These reference intervals and 99th percentile cut-offs will inform clinical decisions in the pediatric cardiology setting.