Direct method for determining the reference values of thyroid function for Mindray analyzers

BACKGROUND: In addition to important individual consequences in patients, errors in the interpretation of the study results in terms of the boundaries in the reference intervals of laboratory markers of thyroid function can lead to hypo- or overdiagnosis and the associated use of drugs, that can have negative effects on the healthcare system. Therefore, the assessment of the relevant reference intervals is crucial in laboratory medicine.

AIM: To determine the reference intervals of thyroid hormones in blood samples of an adult (aged 18–78 years) population of the European part of the Russian Federation using reagent kits for quantitative total and free thyroxine, total and free triiodothyronine, thyroglobulin, and thyroid-stimulating hormones in human clinical samples by immunochemiluminescent method using Mindray analyzers of the CL series (Shenzhen Mindray Bio-Medical Electronics Co., China).

MATERIALS AND METHODS: The study included 269 patients aged 18–78 years. The quantitative determination of the parameters of thyroid function in serum samples was performed on the Mindray Cl 6000i automatic analyzer.

RESULTS: Reliable reference intervals characterizing thyroid function were obtained for thyroid-stimulating hormone (0,64–4,36 µIU/mL), free (2,39–3,79 pg/mL) and total (0,66–1,28 ng/mL) triiodothyronine, free (0,62–1,13 ng/dL) and total (5,04–0,54 µg/dL) thyroxine and thyroglobulin (2,04–48,2 ng/mL) in blood samples of the adult population (aged 18–78 years) of the European part of the Russian Federation.

CONCLUSION: Established reference intervals for diagnostic purposes on the basis of appropriate clinical recommendations must be used. A personalized approach is necessary to interpret the obtained laboratory research data and compare it with anamnesis, data from imaging research methods and clinical patterns.