Vitamin D Homeostasis in Sarcoidosis
University of Texas Southwestern Medical Center
Summary
This study evaluates the relationship between vitamin-D status and severity of sarcoidosis, and the effects of vitamin-D repletion in vitamin-D insufficient patients with sarcoidosis. Half the patients with sarcoidosis who are vitamin-D insufficient will receive standard vitamin-D supplementation via standard regimen while the other half will receive a placebo. Sarcoidosis patients who are vitamin-D sufficient will also act as controls.
Description
Sarcoidosis is a multi-system inflammatory disease characterized by T-helper lymphocyte hyperactivity leading to granulomatous inflammation. The granuloma cells autonomously convert 25-hydroxy-vitamin-D (25OHD) to the active metabolite 1,25-dihydroxy-vitamin-D (1,25OH2D) independent of normal feedback control but dependent on substrate (25OHD) concentration. Circulating 1,25OH2D exerts both anti-inflammatory and mineral metabolic actions. Deficiency of 25OHD limits substrate-dependent 1,25OH2D synthesis, diminishes anti-antigenic innate immunity and augments pro-inflammatory adaptive immunity…
Eligibility
- Age range
- 21+ years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * Stable medical condition defined as no hospitalization or emergency room visit in the previous 3 months * No evidence of active pulmonary or systemic infection * No other active inflammatory disease, * No active malignancy. * Normal serum ionized calcium level Exclusion Criteria: * Hospitalization or emergency room visit in the previous 3 months * Evidence of active pulmonary or systemic infection * Evidence of active other inflammatory disease * Evidence of active malignancy * Elevated serum ionized calcium level
Interventions
- DrugErgocalciferol
Vitamin D2 50,000 units
- DrugPlacebo
Sugar pill manufactured to mimic ergocalciferol 50,000 units
- DrugCalcium Citrate with Vitamin D2
To meet the recommended minimum daily dietary requirements
Location
- University of Texas Southwestern Medical Center, and Parkland Health and Hospital SystemDallas, Texas