Clinical Trial 25-OH Vitamin D, Total, LC/MS/MS

Test Code

991841

CPT Codes
82306<br>Clinical Trial Code

Preferred Specimen

0.5 mL serum

Patient Preparation
Fasting is preferred, but not required

Minimum Volume

0.3 mL

Instructions

Collect blood in a standard red-top serum Vacutainer tube. Allow blood to clot at room temperature. Centrifuge and separate the serum from the cells immediately. Alternatively, collect blood in an SST, allow to clot at room temperature, centrifuge, and remove from the gel within 48 hours.

Transport Temperature

Room temperature

Specimen Stability

Room temperature: 21 days
Refrigerated: 21 days
Frozen: -20° C: 21 days
Frozen: -70° C: 18 months

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Gross hemolysis • Gross lipemia • Heparinized or EDTA Plasma • Icteric • Serum not separated from serum separator tube gel or clot within 48 hours

Methodology
Chromatography • Mass Spectrometry

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: Mon-Fri; Report available: 2 days

Reference Range

See Laboratory Report

Clinical Significance

Measurement of the 25-hydroxyvitamin D [25(OH)D] blood level is the accepted means for determining vitamin D status (N Engl J Med. 2007;357:266-281). Such measurements provide a good index of circulating vitamin D activity in patients not suffering from renal disease. Lower than normal 25(OH)D levels can result from insufficient sun exposure, a dietary deficiency, poor absorption of the vitamin, or impaired metabolism in the liver. A 25(OH)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(OH)D: 25(OH)D3 and 25(OH)D2.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.