目的 分析利妥昔单抗（rituximab, RTX）治疗应用3种免疫抑制剂后仍呈频复发型肾病综合征（frequently relapsing nephrotic syndrome, FRNS）或激素依赖型肾病综合征（steroid‑dependent nephrotic syndrome, SDNS）患儿的有效性及安全性。 方法 收集北京大学第一医院儿童肾内科2014年1月—2023年12月收治的激素联合标准剂量的霉酚酸酯和钙调神经磷酸酶抑制剂治疗后仍呈FRNS或SDNS的患儿。统计其经过RTX治疗后的缓解率、复发率、激素及口服免疫抑制剂的减停情况及RTX应用后的不良反应。 结果 18例患儿纳入该研究，共接受63个疗程的RTX治疗，所有患儿应用RTX后随访时间均>2年，所有入组患儿在应用RTX后均不再表现为FRNS或SDNS。其中11例在首次应用RTX后至最后随访时间未再复发。应用RTX后，所有免疫抑制剂的使用时长均显著减少，复发频率明显下降，差异具有统计学意义（P<0.05）。RTX不良事件多为轻度。 结论 RTX对于应用3种免疫抑制剂仍呈FRNS或SDNS具有良好的疗效及安全性。

Objective To evaluate the efficacy and safety of rituximab (RTX) in children with frequently relapsing nephrotic syndrome (FRNS) or steroid-dependent nephrotic syndrome (SDNS) after treatment with prednisone combined with standard doses of mycophenolate mofetil and a calcineurin inhibitor. Methods A retrospective analysis was conducted on clinical data from pediatric patients admitted to the Department of Pediatric Nephrology, Peking University First Hospital from January 1, 2014 to December 31, 2023. These patients had received prednisone plus standard doses of mycophenolate mofetil and a calcineurin inhibitor but still presented with FRNS or SDNS. Outcomes included remission rate, relapse rate, reduction or discontinuation of steroids and oral immunosuppressants after RTX treatment, and adverse events following RTX. Results Eighteen patients were enrolled, receiving 63 courses of RTX treatment. None presented with FRNS or SDNS after RTX treatment. Among them, 11 patients experienced no relapse from the first RTX dose to the last follow-up. After RTX administration, the duration of use of all immunosuppressants and the relapse frequency were significantly reduced (P<0.05). Most RTX-related adverse events were mild. Conclusions RTX demonstrates good efficacy and safety in children with FRNS or SDNS after treatment with three immunosuppressive agents.