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Vitamin D, calcium, and sarcoidosis
1Department of Pulmonary and Critical Care Medicine, USC School of Medicine, Los Angeles, USA.
Chest
|February 1, 1996
Summary
Sarcoidosis can cause abnormal calcium metabolism, leading to hypercalcemia and hypercalciuria due to excess calcitriol. Early detection and treatment with corticosteroids or other medications are crucial to prevent kidney damage.
Area of Science:
- Nephrology
- Endocrinology
- Pulmonology
Background:
- Sarcoidosis is associated with abnormal calcium metabolism in approximately 10% of patients.
- Hypercalciuria is three times more common than hypercalcemia in sarcoidosis patients.
- The underlying mechanism involves dysregulated calcitriol (1,25-(OH)2-D3) production by activated macrophages in granulomatous inflammation.
Purpose of the Study:
- To summarize the calcium metabolism abnormalities in sarcoidosis.
- To highlight the potential renal complications of undetected hypercalcemia and hypercalciuria.
- To outline treatment strategies for managing these metabolic defects.
Main Methods:
- Review of existing literature on sarcoidosis and calcium metabolism.
- Analysis of the pathophysiology of hypercalcemia and hypercalciuria in sarcoidosis.
- Evaluation of treatment outcomes for various therapeutic interventions.
Main Results:
- Hypercalcemia and hypercalciuria are significant complications of sarcoidosis.
- Dysregulated calcitriol production by activated macrophages is the primary cause.
- Untreated conditions can lead to nephrocalcinosis, kidney stones, and renal failure.
Conclusions:
- Corticosteroids are effective in rapidly correcting the metabolic abnormalities.
- Alternative treatments like chloroquine, hydroxychloroquine, and ketoconazole are indicated for non-responders or those with side effects.
- Prompt management is essential to prevent severe renal sequelae.
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