The efficacy and safety of rituximab in childhood steroid-resistant nephrotic syndrome (SRNS) remains unclear. Therefore, we conducted a retrospective cohort study at 28 pediatric nephrology centers from 19 countries in Asia, Europe, North America and Oceania to evaluate this. Children with SRNS treated with rituximab were analyzed according to the duration of calcineurin inhibitors (CNIs) treatment before rituximab [6 months or more (CNI-resistant) and under 6 months]. Primary outcome was complete/partial remission (CR/PR) as defined by IPNA/KDIGO guidelines. Secondary outcomes included kidney failure and adverse events. Two-hundred-forty-six children (mean age, 6.9 years; 136 boys; 57% focal segmental glomerulosclerosis, FSGS) were followed a median of 32.4 months after rituximab. All patients were in non-remission before rituximab. (146 and 100 children received CNIs for 6 month or more or under 6 months before rituximab, respectively). In patients with CNI-resistant SRNS, the remission rates (CR/PR) at 3-, 6-, 12- and 24-months were 26% (95% confidence interval 19.3-34.1), 35.6% (28.0-44.0), 35.1% (27.2-43.8) and 39.1% (29.2-49.9), respectively. Twenty-five patients were in PR at 12-months, of which 22 had over 50% reduction in proteinuria from baseline. The remission rates among children treated with CNIs under 6 months before rituximab were 42% (32.3-52.3), 52% (41.8-62.0), 54% (44.3-64.5) and 60% (47.6-71.3) at 3-, 6-, 12-, and 24-months. Upon Kaplan-Meier analysis, non-remission and PR at 12-months after rituximab, compared to CR, were associated with significantly worse kidney survival. Adverse events occurred in 30.5% and most were mild. Thus, rituximab enhances remission in a subset of children with SRNS, is generally safe and CR following rituximab is associated with favorable kidney outcome.
Managing primary or even secondary glomerulonephritis remains a challenge to many nephrologists. In primary focal segmental glomerulosclerosis (FSGS) with heavy proteinuria, renin aldosterone system blockade and high dose of oral prednisolone is the mainstay of treatment. Other immunosuppressive medications like Cyclophosphamide, Cyclosporine A and Mycophenolate Mofetil (MMF) are warranted if a complete remission is not achieved. We illustrate a case of 21 year old gentleman with primary FSGS that was difficult to achieve remission despite on high dose steroid and oral Cyclophosphamide. He was also not responsive to a combination of MMF and Cyclosporine A (CSA) and even throughout the therapy he developed significant steroid and CSA toxicity. He presented to our center with severe nephrotic syndrome and acute kidney injury requiring acute haemodialysis. Despite re-challenged him again on high dose prednisolone, total of 2.4g of intravenous Cyclophosphamide, and MMF, he failed to achieve remission. He was subsequently given intravenous Rituximab 500mg/weekly for 4 doses and able to attained remission for 1 year. He relapsed again and a second course of Rituximab 500mg/weekly for 6 doses were given to attain remission. This case demonstrates the difficulty in managing refractory steroid dependent FSGS and we found that Rituximab is proven beneficial in this case to induce remission.