Reference TSH intervals in children and adolescents

The determination of thyroid-stimulating hormone (TSH) is a reliable test in the diagnosis of thyroid dysfunction. When interpreting the results of quantitative studies, clinicians and laboratory specialists most often resort to assessing the compliance of the result with reference intervals (RI). At the same time, each laboratory must determine them for the analytes being measured itself, based on the characteristics of the examined contingent, the characteristics of the analytical systems used, achieving the necessary diagnostic effectiveness of the methodology, and its own practical and economic capabilities. A retrospective analysis of TSH results obtained from patients under the age of 19 years was performed for 54970 patients without hypothyroidism, thyrotoxicosis and pituitary disorders. For this work, reagent kits “Roche Cobas”, “Mindray” and “Beckman Coulter” (ICLA) were used. As a result, RI was established for the study of TSH for three sets of reagents with appropriate equipment and for four age groups: 1 day – 6 months, 6 months – 7 years, 7–14 years, 14–19 years. This makes it possible to use RI as a screening for possible developmental pathology in childhood and to determine the limits of clinical decisions.