[Treatment of children with steroid-dependent nephrotic syndrome with rituximab]

Abstract

Objective: To investigate the effects of rituximab (RTX) in children with steroid-dependent nephrotic syndrome.

Method: Five cases of children with steroid-dependent nephrotic syndrome seen from May 2012 to February 2013 in whom only steroid plus calcineurin inhibitor was effective and the disease recurred on reduction of dose were enrolled into this study, including 3 males and 2 females. Calcineurin inhibitors were stopped and steroids was changed to full dose. After the general condition improved, RTX was given at a dose of 375 mg/m(2), once a week for a total of three times for one course. After urine protein became negative for five days, the dose of steroid was changed to 2 mg/kg every other day, thereafter the dose was reduced by 5 mg per every 2 weeks, until discontinuation. After regular monitoring, when peripheral blood B cells were ≥ 3%, a second RTX was added.

Result: Urine protein was negative in 2-7 days in 5 patients after the first RTX treatment. Before treatment B lymphocytes in peripheral blood was 7.8% to 13.0% and after the first course of RTX treatment decreased to 0 in the first 6 to 8 months at the beginning of recovery, while in the first 7 to 10 months to 3.3%-6.1%, after a second RTX was given, B lymphocytes were reduced to 0, but in two cases (cases 1 and 3) B lymphocytes rose again at 16 and 17 months, in the first 17 and 18 months rose to 4.16% and 4.17%, RTX was given once again respectively. B lymphocytes were reduced to 0 again. Currently the 5 patients continued to be negative for urine protein, maintaining remission for 12 to 20 months.RTX infusion had no significant side effects, and side effects of steroid and calcineurin inhibitor disappeared.

Conclusion: In children with steroid-dependent and only calcineurin inhibitor effective nephritic syndrome, relapse may still occur after improvement of nephrotic syndrome, after the first RTX treatment, regular monitoring of B lymphocytes, RTX supplementary treatment in advance can help discontinuation of steroids and immunosuppressive agents and maintain remission.