Test Code 625
Test Details
Vitamin D, 25-OH
25-hydroxy vitamin D is a hormone precursor that promotes bone, calcium and phosphorus metabolism.
Methodology
Antibody-based chemiluminescence
Patient Preparation
None
Preferred Specimen
1.0 mL serum (0.5 mL minimum) collected in serum separator tube (SST/Tiger Top)
Alternate Specimen
Dried Blood collected on an AdvanceDx 100 card
Transport Temperature
Refrigerated (ship on frozen cold packs)
Stability
Refrigerated: 5 days
Lab Values
Vitamin D, 25-OH
- Low: <30 ng/mL
- Mid: 30–100 ng/mL
- High: >100 ng/mL
Clinical Significance
Vitamin D, 25-OH
Vitamin D insufficiency is associated with:1
- Secondary hyperparathyroidism
- Muscle weakness with increased fall risk
- Myalgias
Vitamin D insufficiency may be associated with:2-4
- Deleterious effects on cardiovascular system
- Impaired pancreatic function
- Increased mortality
References:
- Muscogiuri G, Sorcie GP, Ajjan R, et al. Can vitamin D deficiency cause diabetes and cardiovascular diseases? Present evidence and future perspectives. Nutr Metab Cardiovasc Dis. 2012;22(2):81-7.
- Goodman N, Cobin RH. Reproductive disorders. In: Camacho PM, Gharib H, Sizemore GW, eds. Evidence-Based Endocrinology. 3rd ed. Philadelphia, PA: Lippincott Williams & Wilkins. 2012:190-228.
- Castro MR, Gharib H. Thyroid disorders. In: Camacho PM, Gharib H, Sizemore GW, eds. Evidence-Based Endocrinology. 3rd ed. Philadelphia, PA: Lippincott Williams & Wilkins. 2012:43-80.
- Garber JR, Cobin RH, Gharib H, et al. Clinical practice guidelines for hypothyroidism in adults: cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association. Endocr Pract. 2012;18(6):988-1028.
Treatment Options
Vitamin D, 25-OH
- Vitamin D, 25-OH – High levels indicated toxic levels of vitamin D. Consider discontinuing vitamin D supplements.
- Vitamin D, 25-OH – Low vitamin D supplements. Vitamin D supplements can increase low blood levels of vitamin D, which have been associated with an increased risk of CVD and diabetes. Vitamin D supplements are frequently taken together with calcium to help maintain bone and muscle strength.
