25-OH Hydroxy Vitamin D (Ergocalciferol D2) details
What 25-OH Hydroxy Vitamin D (Ergocalciferol D2) shows
25-Hydroxyvitamin D2 is the circulating form of vitamin D2 (ergocalciferol), which comes from some fortified foods, mushrooms and certain supplements, including the high-strength vitamin D that is often prescribed. Your body does not make D2 itself, so many people have little or none. Measuring D2 separately from D3 shows whether a D2 supplement is being absorbed and how much it adds to your total 25-hydroxyvitamin D. A low or undetectable D2 result is normal if you are not taking D2, and it does not mean vitamin D deficiency on its own. Your overall vitamin D status is judged from the total of D2 and D3, read alongside calcium when relevant.
Tests that include 25-OH Hydroxy Vitamin D (Ergocalciferol D2)
Vitamin D originating from dietary and endogenous sources is converted to 25-hydroxyvitamin D in the liver, and subsequently to 1, 25-dihydroxyvitamin D in the kidney. Measurement of both the 1, 25-Dihydroxy and 25-Hydroxy forms provide insights into a variety of medical conditions such Vitamin D status in renal failure, differential diagnosis of primary, secondary and tertiary hyperparathyroidism. Differential diagnosis of hypercalcemia and type I and II inherited rickets.
- Vitamin D, 25-OH, Total The combined measure of both major forms of vitamin D (D2 and D3) in your blood — the standard test used to assess overall vitamin D status.
- Calcitriol (1,25 di-OH Vitamin D) The active, hormone form of vitamin D that directly regulates calcium absorption. Tested less often than 25-OH vitamin D, mainly for kidney or calcium-regulation disorders.
- 25-OH Hydroxy Vitamin D (Cholecalciferol D3) The vitamin D3 portion of your 25-hydroxyvitamin D, coming from sunlight on your skin, animal foods and most supplements, used to assess vitamin D status.
- 25-OH Hydroxy Vitamin D (Ergocalciferol D2) The vitamin D2 portion of your 25-hydroxyvitamin D, which comes mainly from plant-based sources and prescription or some over-the-counter supplements.
- Vitamin D2, 1,25 (OH)2 Measures the active, hormone form of vitamin D made from vitamin D2, reported as part of a total 1,25-dihydroxyvitamin D (calcitriol) result.
- Vitamin D3, 1,25 (OH)2 Measures the active, hormone form of vitamin D made from vitamin D3, reported as part of a total 1,25-dihydroxyvitamin D (calcitriol) result.
QuestAssureD 25-Hydroxyvitamin D Test - This test measures the levels of Vitamin D in the body, which is crucial for bone health. It checks for Vitamin D activity, except in cases of renal disease. Low levels might indicate a dietary deficiency, poor absorption, or liver issues, leading to bone diseases like rickets and osteomalacia. High levels could cause hypercalcemia. The test specifically measures the two common forms of Vitamin D: 25-OH D3 and 25-OH D2.
- Vitamin D, 25-OH, Total The combined measure of both major forms of vitamin D (D2 and D3) in your blood — the standard test used to assess overall vitamin D status.
- 25-OH Hydroxy Vitamin D (Cholecalciferol D3) The vitamin D3 portion of your 25-hydroxyvitamin D, coming from sunlight on your skin, animal foods and most supplements, used to assess vitamin D status.
- 25-OH Hydroxy Vitamin D (Ergocalciferol D2) The vitamin D2 portion of your 25-hydroxyvitamin D, which comes mainly from plant-based sources and prescription or some over-the-counter supplements.
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