Cardio IQ® Vitamin D, 25-Hydroxy

Test Code

91735

CPT Codes
82306

Includes

Vitamin D, 25-OH, Total
Vitamin D, 25-OH, D₃
_{⁠⁠⁠⁠⁠⁠⁠}Vitamin D, 25-OH, D₂

Preferred Specimen

0.5 mL serum

Patient Preparation
Fasting preferred, but not required

Minimum Volume

0.2 mL

Instructions

Minimize sample exposure to direct sunlight.
SST RF -
1. Gently invert 5X (Do not shake!).
2. Let blood clot for 30 min. at room temperature.
3. Centrifuge for 10 min.
4. Store and transport RF.

Transport Temperature

Refrigerated (cold packs)

Specimen Stability

Room temperature: 21 days
Refrigerated: 21 days
Frozen: 185 days

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

Specimens other than serum • Improper labeling • Samples not stored properly • Samples older than stability limits • Gross hemolysis

Methodology
Chromatography/Mass Spectrometry

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics Cardiometabolic Center of Excellence at Cleveland HeartLab. 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

Night Sets up 7 days a week.

Reference Range

Vitamin D, 25-OH, Total

30-100 ng/mL

25-OHD3 indicates both endogenous production and supplementation. 25-OHD2 is an indicator of exogenous sources, such as diet or supplementation. Therapy is based on measurement of Total 25-OHD, with levels <20 ng/mL indicative of Vitamin D deficiency, while levels between 20 ng/mL and 30 ng/mL suggest insufficiency. Optimal levels are ≥30 ng/mL.

Vitamin D, 25-OH, D3	Not established
Vitamin D, 25-OH, D2	Not established

Clinical Significance

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.

Performing Laboratory
Cleveland HeartLab, Inc
6701 Carnegie Avenue Suite 500
Cleveland, OH 44103-4623

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.