Alfacalcidol plus calcium versus cholecalciferol in glucocorticoid-exposed children with nephrotic syndrome: a randomized controlled trial

Aims This study sought to explore the bone metabolism clinical features of pediatric nephrotic syndrome (NS) patients receiving glucocorticoid (GC) therapy and evaluate the bone-protective and renal-protective efficacy of alfacalcidol in this cohort. Methods A prospective randomized cohort study was conducted at the Department of Nephrology, Guangzhou Women and Children’s Medical Center, enrolling 86 children from January 2021 to June 2022. Participants were randomized into two groups (n = 43 each): the alfacalcidol group administered 0.05 µg/kg alfacalcidol plus 300 mg calcium daily, and the control group given 400 IU vitamin D3 plus 300 mg calcium daily. Primary outcomes included bone mineral density (BMD) and cumulative GC dose, measured at baseline, 3 months, 6 months, and study endpoint. Secondary outcomes covered bone metabolism biomarkers (type I collagen C‑terminal telopeptide and type I procollagen N‑terminal propeptide), urine protein‑to‑creatinine ratio, and proteinuria remission status. Results Multivariate regression identified cumulative GC dose as a risk factor for BMD reduction, while alfacalcidol treatment correlated with BMD improvement. Lumbar spine BMD increased by 0.028 ± 0.008 g/cm² in the alfacalcidol group versus 0.002 ± 0.008 g/cm² decrease in the control group (p = 0.035). Alfacalcidol recipients had lower cumulative GC doses, shorter time to initial urinary protein negativity (7 vs. 11 days, p = 0.004), higher 1‑year GC discontinuation rate (67.9% vs. 38.7%, p = 0.025), lower proteinuria relapse rate (7.9% vs. 41.9%, p = 0.045), and more favorable proteinuria remission survival curves (p = 0.035). Conclusions Alfacalcidol may have potential bone-protective and renal-protective effects in pediatric NS patients undergoing GC therapy (Trial registration: ChiCTR2200055790).