Age-specific reference values for the 5th generation cardiac troponin T assay in Chinese children

Abstract

The clinical use of the cardiac troponin T (cTnT) assay was limited to the adult population in the diagnosis and prognosis of myocardial injury. However, emerging studies indicated its significant value in the assessment of pediatric cardiology, and it has been routinely measured in most hospitals. Our study investigated the normative values of cTnT in Chinese children and reported the age-specific 99th percentile cut-off for them.A total of 1280 apparently healthy Chinese children were enrolled in our study. Serum levels of cTnT were analyzed on the Roche Elecsys Troponin T Gen 5 STAT assay. According to the Clinical and Laboratory Standards Institute C28-A3 guideline, the 99th percentile upper reference limits (URLs) with 90% confidence intervals (CIs) were calculated in different age subgroups.The 99th percentile URL was 38 (90%CI: 37.0-51.0) ng/L for 1 to <4months old, 26 (90%CI: 25.2-28.5) ng/L for 4 to ≤ 12months old, and 12 (90%CI: 11.1-12.9) ng/L for 1 to 18 years old, respectively. For subjects aged from 1 to 18years, boys had slightly higher cTnT levels than girls (P = .003), while our assay could not measure low cTnT concentrations (≥the limit of detection) in 50% girls.Our study provided age-specific URLs of cTnT for Chinese children, with the 5th generation cTnT assay from Roche Diagnostics. It had significant clinical implications in the interpretation and use of test results for pediatric cardiology.

Figure 1. Flow diagram showing the process of the inclusion of apparently healthy children.

Figure 2. Concentrations of cTnT in children under different age stages and gender (male: □, female:  ). The distribution of cTnT in children (0-18 years) was shown in (A). Concentrations of cTnT and its linear correlation with age of months in children (≤ 12 months) was shown in (B). The linear association in children (≤ 12 months) was: cTnT = -2.42^* age (months) + 29.52 (R² = 0.538, P < .001); the linear association in boys (≤ 12 months) was shown: cTnT = -2.26^* age (months) + 28.86 (R² = 0.512, P < .001); The linear association in children (≤ 12months) was shown: cTnT = -2.66^* age (months) + 20.46 (R² = 0.572, P < .001). cTnT = cardiac troponin T.