QuestAssureD™ for Infants, 25‑Hydroxyvitamin D
Also known as: VIT D, Infants
Use
This test provides accurate measurement of 25-hydroxyvitamin D in patients under 3 years by excluding the inactive C3‑epimer, thereby avoiding falsely elevated total vitamin D levels and aiding proper assessment of nutritional and bone health status in infants.
Special Instructions
Intended for patients <3 years of age; uses LC‑MS/MS with separation and exclusion of C3‑epimer of 25‑OH‑vitamin D.
Limitations
Not applicable to patients ≥3 years; immunoassay methods do not detect C3‑epimer, potentially overestimating total vitamin D in infants.
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 62292-8
Result Turnaround Time
2-3 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.5 mL serum
Minimum Volume
0.2 mL
Container
standard red‑top serum vacutainer tube or serum separator tube
Collection Instructions
Allow blood to clot at room temperature; centrifuge and separate serum from cells immediately; serum must be separated from gel or clot within 48 hours if using SST.
Patient Preparation
Fasting specimens are preferred but not required
Causes for Rejection
Gross hemolysis; grossly lipemic; plasma; serum not separated from SST or gel or clot within 48 hours; grossly icteric
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days |
| Refrigerated | 7 days |
| Frozen | 28 days |