The Mayo Clinic Laboratories Distinction
Up to date: September 2013
Revealed: February 2009
Vitamin D is important for robust bones. It additionally has necessary, rising roles in immune operate and most cancers prevention. Deficiencies at any stage of life can have devastating penalties. Equally, vitamin D toxicity ensuing from overmedication may cause severe hypercalcemia. Vitamin D consists of two bioequivalent types:
Till just lately, vitamin D substitute in the US consisted solely of 25-hydroxyvitamin D2. Over the last one to 2 years an rising proportion of 25-hydroxyvitamin D3 substitute is getting used, particularly, in high-dose prescription formulations.
Vitamin D deficiency is extra widespread than beforehand believed, particularly amongst adolescents, ladies, and the aged. For instance, research have proven that greater than 50% of the institutionalized aged and an equal proportion of girls of any age present process remedy for osteoporosis have insufficient ranges of vitamin D.1 Whereas remedy with vitamin supplementation is simple and cheap, many affected people go undiagnosed and untreated.
The full 25-hydroxyvitamin D (25-OH-VitD) stage (the sum of 25-OH-vitamin D2 and 25-OH-vitamin D3) is the suitable indicator of vitamin D physique shops. Though there isn’t any common consensus a couple of remedy reduce level, research recommend 25 to 35 ng/mL because the minimal focus of 25-OH-VitD wanted to keep away from the opposed results of deficiency.2,3,4 In contrast, inhabitants reference ranges don’t correspond with wholesome ranges. In northern latitude places particularly, one-third of the inhabitants could have vitamin D ranges lower than 25 ng/mL on the finish of winter.
Affected person Care
Individuals Who Ought to Be Examined
The next must be examined for vitamin D deficiency:
Affected person Affect
Vitamin D deficiency testing ends in potential impacts:
Advantages of Testing
Vitamin D deficiency testing gives:
Technical Comparability
Ligand-Binding Assays
Technical facets of ligand-binding assays (that’s, radioimmunoassay and aggressive protein-binding assays) embody:
Excessive-Efficiency Liquid Chromatography (HPLC)
Technical facets of HPLC embody:
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Technical facets of LC-MS/MS embody:
How the Mayo Clinic Take a look at Differs
The Mayo Clinic vitamin D deficiency take a look at presents key differentiators:
References
1. Holick MF, Siris ES, Binkley N, et al: Prevalence of vitamin D inadequacy amongst postmenopausal North American ladies receiving osteoporosis remedy. J Clin Endocrinol Metab. 2005;90(6):3215-3224
2. Heaney RP: Vitamin D: how a lot do we want, and the way a lot is an excessive amount of? Osteoporos Int. 2000;11:553-555
3. Chapuy MC, Preziosi P, Maamer M, et al: Prevalence of vitamin D insufficiency in an grownup regular inhabitants. Osteoporos Int. 1997;7:439-443
4. Binkley N, Krueger D, Cowgill CS, et al: Assay variation confounds the prognosis of hypo-vitaminosis D: a name for standardization. J Clin Endocrinol Metab. 2004;89(7):3152-3157
5. Singh, R: Are scientific laboratories ready for correct testing of 25-hydroxy vitamin D? Clin Chem. 2008;54(1):222-223
6. Graham DC, Carter R, Jones J, Berry J: How correct are assays for 25-hydroxyvitamin D? Information from the Worldwide Vitamin D Exterior High quality Evaluation Scheme. Clin Chem. 2004;50:2195-2197
7. Mayo unpublished high quality management knowledge
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