Fast Five Quiz: Vitamin D Practice Essentials

Romesh Khardori, MD, PhD


February 09, 2022

Serum 25(OH)D assessment is recommended to determine vitamin D status. A 25(OH)D level of 12-<20 ng/mL (30-<50 nmol/L) has been used to define vitamin D deficiency. The Endocrine Society suggests that serum 25(OH)D concentrations > 30 ng/mL (> 75 nmol/L) are necessary to maximize the beneficial effects of vitamin D.

Although knowledge of a patient's vitamin D level may be beneficial, routine population screening for vitamin D deficiency is not recommended for individuals who are asymptomatic or not at risk. Vitamin D deficiency is often a silent disease. In adults, vitamin D deficiency can lead to chronic hypocalcemia and hyperparathyroidism. Patients may report chronic muscle aches and pains, mood changes, and fatigue.

Although not always required for the diagnosis of vitamin D insufficiency, serum parathyroid hormone level may be used to help establish the diagnosis of vitamin D insufficiency. Often, patients with vitamin D insufficiency have a corresponding elevated parathyroid hormone, indicating secondary hyperparathyroidism. An inverse relationship exists between parathyroid hormone and 25(OH)D levels. Usually, parathyroid hormone levels decrease after the correction of a vitamin D insufficiency.

Learn more about the workup of vitamin D deficiency.


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