Biomarker Lens

Biomarkers · Chemical

Vitamin D

What it measures

Also listed as
calcidiol, vitamin d 25-hydroxy, 25-oh vitamin d, 25-hydroxy vitamin d
Tests in the graph that measure it
8

A plain-language description with its source has not been added for this biomarker yet. What the laboratories say about the tests that measure it is below.

Tests that measure Vitamin D

Calcitriol 125-Dihydroxyvitamin D

Laboratory
Quest Diagnostics
Test code
16558
Specimen
Serum
Fasting
Not stated as required

What the laboratory says this test is for

This test measures the bioactive form of vitamin D. It is used in the differential diagnosis of hypocalcemia and to monitor patients with renal osteodystrophy or chronic renal failure. This test is not suitable for diagnosis of vitamin D deficiency and monitoring supplementation in most patients. The 25-hydroxyvitamin D test is the recommended test for those purposes (N Engl J Med. 2007;357:266-281).

Quest Diagnostics test directory, test code 16558

Post COVID-19 Panel

Laboratory
Quest Diagnostics
Test code
11454
Specimen
See individual tests
Fasting
Not stated as required

What the laboratory says this test is for

About 10-30% of patients continue with lingering symptoms four or more weeks after COVID-19 infection, including those who had mild, or no symptoms termed as post-COVID conditions. The Centers for Disease Control (CDC) provided Interim Guidance for Assessment and Testing for Evaluating and Caring for Patients with Post-COVID Conditions. The CDC recommends laboratory testing be guided by the patient history, physical examination, and clinical findings. A basic panel of laboratory tests might be considered for patients with ongoing symptoms to assess for conditions that may respond to treatment, until more information and evidence is available for specific laboratory testing for post-COVID conditions. This panel is to be considered for persistent symptoms if basic testing such as Complete Blood Counts, Basic Metabolic Profile, and Liver Function Tests has been completed.

Quest Diagnostics test directory, test code 11454

QuestAssureD 25-Hydroxy and Calcitriol 125-Dihydroxyvitamin D

Laboratory
Quest Diagnostics
Test code
16761
Specimen
Serum
Fasting
Required

What the laboratory says this test is for

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.

Quest Diagnostics test directory, test code 16761

Cardio IQ Vitamin D 25-Hydroxy

Laboratory
Quest Diagnostics
Test code
91735
Specimen
Serum
Fasting
Required

What the laboratory says this test is for

Measurement of serum 25-OH vitamin D concentrations provide a good index of circulating vitamin D activity in patients not suffering from renal disease. Lower than normal 25-OH vitamin D levels can result from a dietary deficiency, poor absorption of the vitamin or impaired metabolism of the sterol in the liver. A 25-OH vitamin D deficiency can lead to bone diseases such as rickets and osteomalacia. Above normal levels can lead hypercalcemia. This assay employs liquid chromatography tandem mass spectrometry to independently measure and report the two common forms of 25-hydroxy vitamin D: 25OH D3 - the endogenous form of the vitamin and 25OH D2 - the analog form used to treat 25OH Vitamin D3 deficiency.

Quest Diagnostics test directory, test code 91735

Post COVID-19 Expanded Panel

Laboratory
Quest Diagnostics
Test code
11453
Specimen
See individual tests
Fasting
Not stated as required

What the laboratory says this test is for

About 10-30% of patients continue with lingering symptoms four or more weeks after COVID-19 infection, including those who had mild, or no symptoms termed as post-COVID conditions. The Centers for Disease Control (CDC) provided Interim Guidance for Assessment and Testing for Evaluating and Caring for Patients with Post-COVID Conditions. The CDC recommends laboratory testing be guided by the patient history, physical examination, and clinical findings. A basic panel of laboratory tests might be considered for patients with ongoing symptoms to assess for conditions that may respond to treatment, until more information and evidence is available for specific laboratory testing for post-COVID conditions. This panel is to be considered for basic testing if no previous testing was performed.

Quest Diagnostics test directory, test code 11453

QuestAssureD for Infants 25-Hydroxyvitamin D

Laboratory
Quest Diagnostics
Test code
91935
Specimen
Serum
Fasting
Required

What the laboratory says this test is for

While measurements of 25(OH)D provide a good index of circulating Vitamin D activity in patients not suffering from renal disease, for infants less than 3 years of age it is important to remove circulating levels of the inactive c3-epimer of Vitamin D from the sample so that total Vitamin D levels are not falsely elevated. Falsely elevated results could erroneously make the child appear to be within normal limits and result in potential under-treatment. Levels of c3-epimer in older children and adults are usually negligible and do not cause falsely elevated Vitamin D results.This assay employs advanced liquid chromatography - tandem mass spectrometry, which enables the chromatographic separation of the c3-epimer from 25-OH Vitamin D, thereby allowing accurate measurement in the presence of c3-epimer. While this assay will produce accurate Vitamin D results on patients of any age, it is specifically indicated for infants less than 3 years of age.

Quest Diagnostics test directory, test code 91935

Diabetes Advancing Chronic Kidney Disease Management Panel

Laboratory
Quest Diagnostics
Test code
91713
Specimen
Serum
Fasting
Not stated as required

What the laboratory says this test is for

This panel is designed for individuals diagnosed as having diabetes mellitus whose kidney disease has advanced to Stage 3/4 impairment. The panel affords the opportunity to assess electrolytes, phosphorus, serum creatinine/eGFR, hemoglobin, microalbumin, parathyroid hormone, calcium, and vitamin D. The grouping of these tests, readily identifiable as elements that adhere to guideline recommendations, is intended to facilitate the ready adherence to professional society clinical practice guidelines. Components of the testing related to the Management of CKD in diabetes, as outlined in the Standards of Medical Care in Diabetes 2013. These recommendations are in broad agreement with those published by the National Kidney Foundation and the American Association of Clinical Endocrinologists.

Quest Diagnostics test directory, test code 91713

QuestAssureD 25-Hydroxyvitamin D D2 D3

Laboratory
Quest Diagnostics
Test code
92888
Specimen
Serum
Fasting
Required

What the laboratory says this test is for

Measurement of serum 25-OH vitamin D concentrations provide a good index of circulating vitamin D activity in patients not suffering from renal disease. Lower than normal 25-OH vitamin D levels can result from a dietary deficiency, poor absorption of the vitamin or impaired metabolism of the sterol in the liver. A 25-OH vitamin D deficiency can lead to bone diseases such as rickets and osteomalacia. Above normal levels can lead to hypercalcemia. This assay employs liquid chromatography tandem mass spectrometry to independently measure and report the two common forms of 25-hydroxy vitamin D: 25-OH D3 - the endogenous form of the vitamin and 25-OH D2 - the analog form used to treat 25-OH Vitamin D3 deficiency.

Quest Diagnostics test directory, test code 92888

About this page

Everything above is drawn from the named sources and shown as they published it. Reference ranges belong to the laboratory that issued them and the population it named; they are not a universal normal. This page describes the biomarker in general and does not interpret anyone's result. For your own numbers, talk to a clinician, or use Aumnivida, which reads the same graph next to your records.

Found an error? Write to hello@biomarkerlens.com with the page link and the source that contradicts it.