Vitamin D 25-Hydroxy (D2+D3 Fractionated) Blood Test, LC/MS-MS

What is the purpose of this test?

The Vitamin D 25-Hydroxy (D2+D3 Fractionated) Blood Test, LC/MS-MS, is a highly accurate diagnostic tool used to assess vitamin D status by measuring both vitamin D2 and D3 levels in the blood. Unlike standard immunoassays, this test employs liquid chromatography-tandem mass spectrometry (LC-MS/MS), considered the gold standard for vitamin D testing due to its precision and ability to differentiate between the two forms of vitamin D.

Vitamin D is crucial for maintaining bone health, immune function, and overall well-being. Deficiencies or imbalances can lead to conditions such as osteoporosis, rickets, and increased susceptibility to infections. By fractionating the D2 and D3 forms, this test provides a detailed profile of vitamin D status, aiding in the diagnosis and management of various health conditions.

The Vitamin D 25-Hydroxy (D2+D3 Fractionated) Blood Test, LC/MS-MS, includes:

• Vitamin D2 (ergocalciferol): A form of vitamin D primarily obtained from plant sources and fortified foods. It is less potent than vitamin D3 but contributes to overall vitamin D levels.
• Vitamin D3 (cholecalciferol): The form of vitamin D synthesized by the skin upon exposure to sunlight and found in animal-based foods. It is more potent than vitamin D2 and is the preferred form for supplementation.
• Total 25-Hydroxyvitamin D: The sum of D2 and D3 levels, representing the body's total vitamin D status and the most reliable indicator of vitamin D sufficiency.

Who should get this test?

Individuals who may benefit from the Vitamin D 25-Hydroxy (D2+D3 Fractionated) Blood Test, LC/MS-MS include:

• Those experiencing unexplained bone pain or muscle weakness.
• Individuals with a history of fractures or low bone density.
• People with limited sun exposure or those living in northern latitudes.
• Individuals with darker skin tones, as they may have reduced vitamin D synthesis.
• People with malabsorption disorders, such as celiac disease or Crohn's disease.
• Individuals on medications that affect vitamin D metabolism, like anticonvulsants or glucocorticoids.
• Patients undergoing treatment for osteoporosis or other bone-related conditions.

When should I order the Vitamin D 25-Hydroxy (D2+D3 Fractionated) Blood Test, LC/MS-MS?

Individuals may consider ordering this test if they have symptoms or exposure concerns related to vitamin D deficiency. Symptoms to consider:

• Bone pain or tenderness, especially in the ribs, spine, or legs.
• Muscle weakness or cramps.
• Fatigue or general malaise.
• Frequent infections or illnesses.
• Depression or mood changes.
• Slow wound healing.

If you have these symptoms or suspect a vitamin D deficiency, the Vitamin D 25-Hydroxy (D2+D3 Fractionated) Blood Test, LC/MS-MS, can provide valuable information to guide you and your doctor in managing your health and ensuring optimal vitamin D levels.