Age partitioned and continuous upper reference limits for Ortho VITROS High Sensitivity Troponin I in a healthy
Joel Smith1, Vasiliki Karlaftis2, Stephen Hearps2
1The Royal Children's Hospital, Parkville, VIC, Australia.
Insights
New reference limits for high-sensitivity troponin I (hs-TnI) in children are now available. These pediatric cardiac troponin levels help clinicians assess myocardial injury in neonates and children.
Area of Science:
- Pediatric Cardiology
- Biomarker Assays
- Clinical Diagnostics
Background:
- Cardiac troponin (cTn) elevation defines myocardial injury in adults, but pediatric reference limits are not well-established.
- Interpreting cTn in children is challenging due to assay variability and lack of age-specific data.
- High-sensitivity troponin I (hs-TnI) assays require specific pediatric reference ranges for accurate clinical use.
Purpose of the Study:
- To establish age-partitioned and continuous 99th percentile reference limits for the Ortho VITROS hs-TnI assay in a pediatric population.
- To provide clinicians with reliable data for assessing myocardial injury in neonates, infants, and children.
- To address the lack of well-defined upper reference limits for hs-TnI in healthy children.
Main Methods:
- Utilized 328 pediatric blood samples from healthy individuals aged 0 to 17.8 years.
- Derived age-partitioned reference limits following CLSI EP28-A3C guidelines.
- Established continuous reference limits based on the HAPPI Kids Study methodology.
Main Results:
- hs-TnI levels are significantly elevated at birth, declining within the first six months of life.
- The 99th percentile upper reference limit was 72 ng/L for ages 0-3 months and 9 ng/L for ages 3 months to 18 years.
- Continuous upper 99th percentile reference limits showed comparable results to partitioned limits.
Conclusions:
- Established partitioned and continuous 99th percentiles for hs-TnI using the Ortho VITROS assay in healthy children.
- These reference limits will aid clinicians in the accurate assessment of myocardial injury in pediatric patients.
- Provides crucial diagnostic support for pediatric cardiac troponin interpretation.
Objectives:
In adults, the elevation of cardiac troponin (cTn) above the 99th percentile upper reference limit defines myocardial injury. The use and interpretation of cTn in a paediatric population, however, is difficult given the 99th percentile for different assays is not well established. Using paediatric blood samples from healthy neonates, infants and children we derived continuous and partitioned 97.5th and 99th percentiles for the Ortho VITROS hs-TnI assay.
Methods:
A total of 328 samples for infants, children and adolescents aged 0-17.8 years were obtained. Age partitioned reference limits were derived in accordance with CLSI EP28-A3C. Continuous reference limits were established as described previously by the HAPPI Kids Study team.
Results:
hs-TnI as measured by the Ortho VITROS Assay is highly elevated above the adult 99th percentile at birth and declines to lower levels within the first 6 months of life. The 99th centile upper reference limit for ages 0-3 months was 72 ng/L (90% CI: 52-91) and 9 ng/L (90% CI: 5.2-17.4) for ages 3 months to 18 years. Continuous upper 99th centile reference limits were comparable.
Conclusions:
Partitioned and continuous 99th percentiles for hs-TnI were derived for the new Ortho VITROS assay in healthy neonates and older children. This will assist clinicians to appropriately assess for the presence of myocardial injury in this population.
