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 and monitoring supplementation in most patients. The 25-hydroxyvitamin D test is the recommended test for those purposes (N Engl J Med. 2007;357:266-281). 25-OH Vitamin D level is performed by PHL and should be ordered as test code VD251. 1,25-dihydroxy Vitamin D is performed by Quest Diagnostics and should be ordered as test code VITD2.
Avoid Hemolysis
1. Allow blood to clot (30 minutes) at ambient temperature
2. Centrifuge and separate the serum from the cells.
Grossly hemolyzed; Lipemic; Icteric specimens; Plasma
Vitamin D3, 1,25(OH)2:
No age/sex specific ranges for this test.
Vitamin D2, 1,25(OH)2:
No age/sex specific ranges for this test.
Vitamin D, 1,25(OH)2, Total, LC/MS/MS:
1 year to 9 years: 31-87 pg/mL
10 years to 13 years: 30-83 pg/mL
14 years to 17 years: 19-83 pg/mL
Adults: 18-72 pg/mL
Vitamin D3, 1,25(OH)2 indicates both endogenous production and supplementation.
Vitamin D2, 1,25(OH)2 is an indicator of exogenous sources, such as diet or supplementation.
Interpretation and therapy are based on measurement of Vitamin D, 1,25 (OH)2, Total.
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 and monitoring supplementation in most patients. The 25-hydroxyvitamin D test is the recommended test for those purposes (N Engl J Med. 2007;357:266-281). 25-OH Vitamin D level is performed by PHL and should be ordered as test code VD251. 1,25-dihydroxy Vitamin D is performed by Quest Diagnostics and should be ordered as test code VITD2.
5 to 8 days
01422846
82652