Effect of Vitamin D3 Supplementation on Interferon-Gamma Levels in Children with Nephrotic Syndrome

Abstract

Introduction: Nephrotic syndrome (NS) in children commonly leads to vitamin D deficiency through urinary loss of vitamin D–binding protein and albumin. Vitamin D regulates cytokine production, including interferon-gamma (IFN-γ), a key Th1 pro-inflammatory cytokine in NS immune dysregulation. Evidence on vitamin D supplementation's effect on IFN-γ levels in pediatric NS remains limited.

Objective: This study aimed to evaluate the effect of vitamin D3 supplementation on interferon-gamma levels in children with nephrotic syndrome.

Methods: A double-blind randomized controlled trial was conducted in children aged 1–18 years with nephrotic syndrome at two hospitals in Makassar, Indonesia. Participants received standard therapy with vitamin D3 supplementation of 400 IU/day or 1000 IU/day for four weeks. Serum 25-hydroxyvitamin D [25(OH)D] and interferon-gamma levels were measured before and after supplementation. Data analysis used Mann–Whitney and Wilcoxon tests (p < 0.05).

Results: A total of 59 participants completed the study (30 in the 400 IU group and 29 in the 1000 IU group). Baseline IFN-γ levels were comparable between groups. After four weeks of supplementation, serum vitamin D levels increased significantly in both groups (p < 0.05), although most participants remained below the normal range. The median increase in vitamin D levels was 4.7 ng/mL in the 400 IU group and 5.1 ng/mL in the 1000 IU group. Changes in IFN-γ levels were not statistically significant between groups.

Conclusion: Vitamin D3 supplementation improved serum vitamin D levels in children with nephrotic syndrome but did not significantly affect interferon-gamma levels within four weeks of intervention. Higher doses or longer supplementation may be required to achieve meaningful immunomodulatory effects.