Reference ranges are established for total 1,25-dihydroxy vitamin D. Values for subcomponents D2 (derived from plant or fungal sources) and D3 (derived from human or animal sources) are provided for informational purposes only.
Clinical Significance
This test measures the bioactive form of vitamin D. It is used in the differential diagnosis of hypocalcemia and to monitor patients with renal osteodystrophy or chronic renal failure. This test is not suitable for diagnosis of vitamin D deficiency. The Vitamin D, 25-hydroxy test 17306 is the recommended test for those purposes.