Effect of Combined Gluten-Free, Dairy-Free Diet in Children With Steroid-Resistant Nephrotic Syndrome: An Open Pilot Trial

Introduction: Steroid-resistant nephrotic syndrome (SRNS) affects both children and adults and has a high rate of progression to end-stage renal disease. Although a subset of patients have well-characterized genetic mutation(s), in the majority of cases, the etiology is unknown. Over the past 50 years, a number of case reports have suggested the potential impact of dietary changes in controlling primary nephrotic syndrome, especially gluten and dairy restrictions. Methods: We have designed a prospective, open-label, nonrandomized, pilot clinical trial, to study the effect of a gluten-free and dairy-free (GF/DF) diet in children with SRNS. The study will be organized as a 4-week summer camp to implement a GF/DF diet in a tightly controlled and monitored setting. Blood, urine, and stool samples will be collected at different time points during the study. Results: The primary end point is a reduction of more than 50% in the urine protein:creatinine ratio. The secondary end points include changes in urine protein, kidney function, and serum albumin, as well as effects in immune activation, kidney injury biomarkers, and gut microbiome composition and function (metagenomic/metatranscriptomic). Conclusion: This study will advance the field by testing the effect of dietary changes in patients with SRNS in a highly controlled camp environment. In addition, we hope the results will help to identify a responder profile that may guide the design of a larger trial for further investigation. Keywords: dairy-free, diet, gluten-free, pediatric summer camp, proteinuria, steroid-resistant nephrotic syndrome