At a glance
| Analyte | 25-hydroxy vitamin D, total |
|---|---|
| Also called | 25-OH Vitamin D, VD-T, Vit D, Vitamin D |
| Method | Competitive chemiluminescence immunoassay |
| Sample type | Serum, Plasma |
| Panel | Bone and metabolic |
| Discipline | CLIA immunoassay |
| Brand | Mindray |
What Vitamin D Total measures
Vitamin D status is assessed by measuring 25-hydroxy vitamin D, the circulating storage form, rather than the active metabolite. This is deliberate and worth understanding: the active form has a short half-life and is tightly regulated, so it can remain normal while stores are severely depleted, which makes it a poor indicator of status. The 25-hydroxy form reflects supply from both sunlight and diet and has a long enough half-life to represent the preceding weeks. A total assay measures both the D2 and D3 forms together, which matters in patients taking supplements, since the two are not always captured equally by every method.
How Philippine laboratories run it
Vitamin D testing has grown substantially in Philippine private laboratories and executive check-up packages, which is somewhat counterintuitive in a tropical country and reflects indoor work patterns, sun avoidance and the use of sun protection more than latitude. Requests are a mix of one-off assessment and monitoring in patients on supplementation, and it is one of the CLIA assays most often ordered by the patient rather than by a specialist. Laboratories adding it should expect steady rather than spiky demand and should plan it alongside the bone panel where they offer one.
Analyzers it runs on
Calibrator, controls and companion tests
Delivered with the rest of the bone and metabolic panel, on the same schedule as Vitamin D Total.
Storage and handling
Refrigerated, upright, and not frozen.
Buying Vitamin D Total in the Philippines
Vitamin D Total is supplied for the CL-2600i and CL-900i. We deliver it with Calcium and Phosphorus, because a run held up waiting on a separate order costs the same shift a stock-out does. Delivery is scheduled against your monthly Vitamin D Total count, so the bench is not rationing tests in the last week of the month. How we plan clia immunoassay supply.
Questions about Vitamin D Total
Why measure 25-OH vitamin D rather than the active form?
Because the active form is tightly regulated and has a short half-life, so it can stay within the reference interval while stores are severely depleted. The 25-hydroxy form is the circulating storage form, has a much longer half-life, and reflects supply over the preceding weeks. It is the appropriate measurement for assessing status, which is what is almost always being asked.
Order Vitamin D Total
Tell us your monthly Vitamin D Total volume and we will quote a supply schedule for CL-2600i. We reply within one business day.
Request a quotation