Vitamin D Status and Clinical Outcomes in Pediatric Idiopathic Nephrotic Syndrome: A Prospective Observational Study from North India

Background: Idiopathic nephrotic syndrome frequently presents with Vitamin D deficiency due to urinary losses of Vitamin D-binding protein. The relationship between Vitamin D status and clinical outcomes remains incompletely understood. Objective: To evaluate Vitamin D status in children with idiopathic nephrotic syndrome and assess its association with remission time and relapse patterns. Materials and Methods: This prospective observational study (October 2022-March 2024) included 60 children aged 1–14 years with idiopathic nephrotic syndrome at a tertiary care center in North India. The study involved 60 patients divided into supplemented (Group I, n = 30) and control (Group II, n = 30) groups. Vitamin D levels were measured at presentation, after 1 month, and at relapse events. Primary outcomes included baseline Vitamin D status, time to remission, and 6-month relapse rates. Results: All participants demonstrated Vitamin D deficiency (51.7%) or insufficiency (48.3%) at presentation. Children with relapses had significantly lower baseline Vitamin D levels compared to those with initial episodes (8.76 ± 2.75 vs. 15.78 ± 2.04 ng/mL, P < 0.001). Despite this association, time to remission was similar between groups with adequate versus inadequate Vitamin D status (11.60±3.2 vs 11.93 ± 3.4 days, p = 0.994). Six-month relapse rates showed no significant correlation with baseline Vitamin D levels ( r = −0.18, P = 0.17). Conclusions: Vitamin D deficiency is universal in pediatric nephrotic syndrome, with lower levels observed in relapsing disease. However, Vitamin D status does not appear to significantly influence time to remission or short-term relapse patterns, suggesting its role may be primarily nutritional rather than therapeutic.