Preferred Specimen(s) 3 mL serum
Instructions The preferred specimen transport temperature is frozen. Room temperature and refrigerated transportation
Transport Container Plastic screw-cap vial
Transport Temperature Frozen
Reject Criteria Received room temperature
Methodology ELISA
Clinical Significance Vitamin D originating from dietary and endogenous sources is converted to 25-hydroxy vitamin D in the liver, and subsequently to 1-, 25-dihydroxyvitamin D in the kidney. Deficiencies of 1-,25-dihydroxyvitamin D, the most active form, cause hypocalcemia, osteomalacia, and related disorders. Measurement is useful in: differentiating primary hyperparathyroidism from hypercalcemia of cancer; distinguishing between vitamin D dependent and vitamin D resistant rickets; monitoring vitamin D status of patients with chronic renal disease; and, assessing compliance to therapy.