Vitamin D resistance in magnesium deficiency

Area of Science:

• Endocrinology
• Mineral Metabolism
• Gastroenterology

Background:

• Hypocalcemia and hypomagnesemia can coexist in patients with gastrointestinal disorders or chronic alcoholism.
• Standard vitamin D therapies (ergocalciferol, dihydrotachysterol) are often ineffective in correcting hypocalcemia in these cases.
• Elevated parathormone levels suggest a potential resistance to its effects on calcium homeostasis.

Purpose of the Study:

• To investigate the role of magnesium in refractory hypocalcemia associated with gastrointestinal disorders and alcoholism.
• To determine the efficacy of magnesium repletion in correcting both hypocalcemia and hypomagnesemia.
• To explore the mechanism by which magnesium influences calcium metabolism.

Main Methods:

• Case series of five patients presenting with hypocalcemia and hypomagnesemia.
• Administration of pharmacological doses of ergocalciferol or dihydrotachysterol.
• Measurement of serum calcium, magnesium, and parathormone levels.
• Administration of magnesium repletion and monitoring of biochemical responses.
• Analysis of mineral balance data.

Main Results:

• Vitamin D therapy failed to correct hypocalcemia in most patients.
• Magnesium repletion effectively corrected both hypomagnesemia and hypocalcemia simultaneously.
• High parathormone levels persisted, indicating impaired calcemic response to parathormone.
• Mineral balance data suggested increased bone mineral mobilization following magnesium repletion.

Conclusions:

• Magnesium plays a crucial role in correcting hypocalcemia, particularly when vitamin D and parathormone actions are impaired.
• Magnesium repletion appears to facilitate calcium release from bone.
• Simultaneous correction of hypomagnesemia and hypocalcemia highlights the interconnectedness of these minerals.