Measuring 25-hydroxyvitamin D in a clinical environment: challenges and needs
1Medical University of South Carolina, Charleston, SC, USA. hollisb@musc.edu
The American Journal of Clinical Nutrition
|August 12, 2008
Summary
Measuring 25-hydroxyvitamin D (25(OH)D) levels is increasingly common. Accurate quantification requires trained operators and participation in quality assessment schemes for reliable diagnostic results.
Area of Science:
- Clinical Chemistry
- Endocrinology
- Laboratory Medicine
Background:
- Circulating 25-hydroxyvitamin D [25(OH)D] assessments have surged in diagnostic use over the last five years.
- Advancements in quantification techniques have led to varied improvements and challenges in accuracy.
Purpose of the Study:
- To provide an overview of available 25(OH)D measurement techniques.
- To compare these techniques and evaluate their clinical utility.
- To discuss the stability of 25(OH)D in biological samples and quality assessment schemes.
Main Methods:
- Review of current techniques for quantifying 25(OH)D.
- Comparison of different measurement methodologies.
- Assessment of clinical utility and diagnostic validity.
- Discussion of sample stability and external quality assessment.
Main Results:
- Most current 25(OH)D assays provide valid results when performed by trained personnel.
- Participation in the Vitamin D External Quality Assessment Scheme is crucial for diagnostic laboratories.
- Circulating 25(OH)D exhibits high stability in stored serum or plasma, enabling longitudinal studies.
Conclusions:
- Accurate 25(OH)D measurement relies on validated techniques, operator proficiency, and quality assurance.
- The stability of 25(OH)D supports its use in long-term epidemiological research.
- Standardized methods and quality control are essential for reliable clinical diagnosis.
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