Determination of prolactin reference intervals in different age groups

BACKGROUND: Clinical diagnostic laboratories (CDL) have at their disposal various automated systems for the measurement of biochemical parameters and markers such as prolactin. Each of the test systems manufactures offers its own alternate design of the method, which makes standardization difficult. In endocrinological practice, the problem of result discrepancies often arises. In hormonal assays, the clinical picture of patients sometimes does not correspond to the reference values provided by the manufacturers, which determines the need to develop the method-specific reference values for a specific population. The difficulty in interpreting basal prolactin levels is not only due to a transient increase in the hormone levels caused by stress or excessive physical exertion, but also due to a significant variability of indicators in the same patient, even if all recommendations for blood sampling are followed.

AIM: The aim of the study to determine the reference values in serum samples of women, men and children of different age groups for the VITROS Immunodiagnostic Systems and compare the results with the “expected prolactin levels” recommended by the method manufacturer

MATERIALS AND METHODS: The monocentric study included 879 serum samples of apparently healthy subjects who were admitted to the Endocrinology Research Center. Measurements were performed using the VITROS ECi 3600 automatic chemiluminescence analyzer (Ortho-Clinical Diagnostics, Great Britain).

RESULTS: For adult men and women reference values were 66–436 and 94–500 mIU/l respectively. When comparing the results of prolactin determination in women and men of the studied cohort with the “expected values” of the VITROS ECi 3600 manufacturer a systematic shift towards an increase in lower and upper limits of the reference values was found in both ­cohorts.

CONCLUSION: The obtained reference values of prolactin can be use in the determination of prolactin in the Russian population for VITROS ECi 3600 Immunodiagnostic Systems.

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