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HelpTest Code LAB536 1,25-Dihydroxyvitamin D, Serum
Test Down Notes
Effective November 19, 2024: This test is temporarily unavailable due to analytic issues. The downtime is expected to be >30 days. Order FV125 as an alternative. See test notification here.
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Reporting Name
1,25-Dihydroxyvitamin D, SSpecimen Type
SerumOrdering Guidance
The 25-hydroxyvitamin D test (25HDN / 25-Hydroxyvitamin D2 and D3, Serum) in serum is the preferred initial test for assessing vitamin D status and most accurately reflects the body's vitamin D stores. In the presence of renal disease or hypercalcemia, testing of 1,25-dihydroxy vitamin D (DHVD) may be needed to adequately assess vitamin D status.
Specimen Required
Patient Preparation: Fasting is preferred for 4 hours but not required.
Collection Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Submission Container/Tube: Plastic vial
Specimen Volume: 1.5 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Reject Due To
| Gross hemolysis | Reject |
| Gross lipemia | OK |
| Gross icterus | OK |
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Serum | Refrigerated (preferred) | 30 days | |
| Frozen | 30 days | ||
| Ambient | 7 days |
Specimen Minimum Volume
0.7 mL
Day(s) Performed
Monday through Friday
Specimen Retention Time
2 weeksReport Available
2 to 5 daysReference Values
Males:
<16 years: 24-86 pg/mL
≥16 years: 18-64 pg/mL
Females:
<16 years: 24-86 pg/mL
≥16 years: 18-78 pg/mL
For International System of Units (SI) conversion for Reference Values, see www.mayocliniclabs.com/order-tests/si-unit-conversion.html
Useful For
As a second-order test in the assessment of vitamin D status, especially in patients with renal disease
Investigation of some patients with clinical evidence of vitamin D deficiency (eg, vitamin D-dependent rickets due to hereditary deficiency of renal 1-alpha hydroxylase or end-organ resistance to 1,25-dihydroxyvitamin D)
Differential diagnosis of hypercalcemia
CPT Code Information
82652
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| DHVD | 1,25-Dihydroxyvitamin D, S | 62290-2 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 8822 | 1,25-Dihydroxyvitamin D, S | 62290-2 |
Supportive Data
The 1,25-dihydroxyvitamin D liquid chromatography tandem mass spectrometry (LC-MS/MS) assay correlates well with the current immunoassay:
-LC-MS/MS=0.95 RIA (pg/mL) + 2.5 pg/mL; correlation coefficient=0.822
-Inter-assay precision: 7 to 12% CV (19 to 287 pg/mL)
-Interferences: C-3 epimers (EPI) of 1,25 dihydroxyvitamin D3 3.0%
Forms
If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:
-General Request (T239)
-Renal Diagnostics Test Request (T830)