Efficacy of rituximab therapy in children with refractory nephrotic syndrome: a prospective observational study in Shanghai

Background: Idiopathic nephrotic syndrome is the most common glomerular disease in children. This study was undertaken to observe the efficacy and side-effects of rituximab (RTX) in treating children with different types of refractory primary nephrotic syndrome. Methods: Twelve patients with steroid dependent nephrotic syndrome (SDNS), frequently relapsing nephritic syndrome (FRNS), and steroid resistant nephrotic syndrome (SRNS) were enrolled in our study. There were obvious drug side-effects, and proteinuria remained difficult to control. RTX was administered at a dose of 375 mg/m(2) body surface area, once or twice weekly. Results: The male to female ratio was 3:1, and the onset age was 1.6-8.9 years. There were 9 patients with steroid sensitive nephrotic syndrome (SDNS or FRNS), and 3 patients with SRNS. There were 7 patients with minimal change disease (MCD), 3 patients with focal segmental glomerular sclerosis (FSGS), 1 with focal proliferative glomerulonephritis, and 1 without renal biopsy. The total effective treatment rate of RTX was 91.67%, and for 77.78% of the patients, steroid dosage could be reduced. Six months before and after RTX infusion, the mean steroid dosage was significantly decreased (P=0.014) and the recurrence number was significantly reduced (P<0.001). The results were better in MCD patients than in FSGS patients (P=0.045). There was no significant difference between FRNS/SDNS and SRNS patients (P=0.175). During RTX administration, 3 patients developed skin rashes, 1 developed hypotension, and. 1 developed a fever. One patient experienced a persistent decrease in serum immunoglobulin level but without serious infection. Conclusion: RTX was effective in the treatment of refractory nephrotic syndrome, and it could significantly reduce the use of steroid and immunosuppressants.