Vitamin D Measurement, the Debates Continue, New Analytes Have Emerged, Developments Have Variable Outcomes
William D Fraser1,2, Jonathan C Y Tang3, John J Dutton3
1Norwich Medical School, University of East Anglia, Norwich Research Park, Floor 2, Bob Champion Research and Education Building, James Watson Road, Norwich, NR4 7UQ, UK. W.Fraser@uea.ac.uk.
Calcified Tissue International
|November 20, 2019
Summary
Advancements in vitamin D metabolite measurement improve clinical diagnosis and research. Measuring metabolites beyond 25-hydroxyvitamin D (25(OH)D) offers new insights into vitamin D metabolism abnormalities.
Area of Science:
- Clinical Chemistry
- Biochemistry
- Endocrinology
Background:
- Increased demand for vitamin D metabolite analysis for clinical diagnosis and research.
- Technological advancements enable separation and quantification of more metabolites and interferences.
- Development of immunoassays and external quality assurance schemes (DEQAS) have improved standardization and comparability.
Purpose of the Study:
- To describe developments in the measurement of commonly analyzed vitamin D metabolites.
- To discuss current analytical approaches, assay differences, and influencing factors.
- To provide an overview of the value and application of measuring metabolites beyond 25-hydroxyvitamin D (25(OH)D).
Main Methods:
- Review of current analytical approaches for vitamin D metabolite measurement.
- Discussion of differences between various assays and their origins.
- Evaluation of the influence of physiological and experimental conditions on measurements.
Main Results:
- Technological progress has enhanced the separation and quantification of vitamin D metabolites.
- Standardization and quality assurance efforts have improved measurement comparability.
- The clinical value of measuring metabolites beyond 25(OH)D is still under investigation.
Conclusions:
- Developments in analytical technologies and standardization have significantly improved vitamin D metabolite measurements.
- Measuring metabolites such as 1,25 dihydroxyvitamin D, 24,25 dihydroxyvitamin D, and free 25OHD may aid in diagnosing vitamin D metabolism abnormalities.
- Further research is needed to confirm the routine clinical utility of measuring these additional metabolites.
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