目的·研究利妥昔单抗（rituximab，RTX）治疗难治性原发性膜性肾病（primary membranous nephropathy，PMN）的临床效果及安全性。方法·回顾性分析复旦大学附属中山医院青浦分院肾内科2018年7月—2022年4月收治的难治性PMN患者（经糖皮质激素联合环孢素、环磷酰胺或他克莫司等免疫抑制剂治疗1年以上仍未达到临床缓解或出现临床复发的患者），使用2剂RTX方案（RTX单次剂量为1 000 mg，2次用药间隔时间为2周；6个月后检测患者外周血B细胞数量，若外周血B细胞数量>5个/μL，则予以追加RTX 1 000 mg）。随访主要观察指标为血白蛋白、血肌酐、尿蛋白肌酐比（urinary protein/creatinine ratio，UPCR）、血磷脂酶A2（phospholipase A2 receptor，PLA2R）抗体、外周血B细胞计数、血清总IgG水平。观察患者主要指标的变化趋势及不良反应，评估治疗方案的临床疗效及安全性。结果·共纳入18例患者，平均年龄为（58.17±16.73）岁，其中男性11例。RTX治疗总剂量为（2 222.22±485.07）mg，RTX治疗后随访时间为（14.9±4.9）个月。末次随访时，血白蛋白较RTX治疗前显著升高［（36.50±5.33）g/L vs （27.61±8.59）g/L，P=0.009］，血肌酐水平稳定（P>0.05），UPCR显著下降［863.30（203.20，2 291.75）mg/g vs 2 954.00（1 458.00，7 260.75）mg/g，P=0.047］，PLA2R抗体显著下降［（44.32±33.71）RU/mL vs （168.40±88.40）RU/mL，P=0.015］，外周血B细胞计数显著下降［（37.89±12.43）个/μL vs （246.40±239.98）个/μL，P=0.009］，血清总IgG水平稳定（P>0.05）。RTX治疗后，8例患者达到完全缓解（44.4%），7例达到部分缓解（38.9%），治疗总体有效率为83.3%；仅有3例患者评估为不缓解（16.7%）。在不良反应方面，1例患者出现输注过敏反应，1例患者发生肺部感染。结论·对于经过传统免疫抑制剂治疗后持续未达到临床缓解或出现临床复发的难治性PMN患者，使用2剂RTX治疗方案可有效诱导该类患者达到临床完全或部分缓解，且安全性良好。

Objective ·To evaluate clinical efficacy and safety of rituximab (RTX) in the patients with refractory primary membranous nephropathy (PMN). Methods ·A retrospective analysis was carried out on the patients with refractory PMN, who had recurred or had not achieved clinical remission after more than 1 year of treatment with glucocorticoid and cyclosporine, cyclophosphamide or tacrolimus, admitted to the Department of Nephrology, Qingpu Branch of Zhongshan Hospital, Fudan University from July 2018 to April 2022. They received 2 doses of RTX. The single dose of RTX was 1 000 mg, and the interval between the two doses was 2 weeks. After 6 months, the numbers of peripheral blood B cells of the patients were detected. If the count of peripheral blood B cells were greater than 5 cell/μL, another 1 000 mg RTX would be added. The main indicators were serum albumin, serum creatinine, urinary protein/creatinine ratio (UPCR), blood antibody against phospholipase A2 receptor (PLA2R) antibody, peripheral blood B cell count, and serum total IgG level. The clinical efficacy and safety of the treatment regimen were evaluated by observing the change of the main indicators of patients and adverse reactions. Results ·A total of 18 patients were included, with an average age of (58.17±16.73) years, including 11 males. The total dose of RTX was (2 222.22±485.07) mg, and the follow-up time after RTX treatment was (14.9±4.9) months. At the last follow-up, the serum albumin level was significantly higher than that before RTX treatment [(36.50±5.33) g/L vs (27.61±8.59) g/L, P=0.009]; the serum creatinine level was stable (P>0.05); the value of UPCR decreased significantly [863.30 (203.20, 2 291.75) mg/g vs 2 954.00 (1 458.00, 7 260.75) mg/g, P=0.047]; the PLA2R antibody decreased significantly [(44.32±33.71) RU/mL vs (168.40±88.40) RU/mL, P=0.015]; the peripheral blood B cell count decreased significantly [(37.89±12.43) cell/μL vs (246.40±239.98) cell/μL, P=0.009]; the total blood IgG level was stable (P>0.05). After RTX treatment, 8 patients achieved complete remission (44.4%), 7 patients achieved partial remission (38.9%), and the overall effective rate was 83.3%; only 3 patients were unrelieved (16.7%). In terms of adverse reactions, 1 patient had transfusion allergy reaction, and 1 patient had pulmonary infection. Conclusion ·For the patients with refractory PMN who have relapse or do not relieve after traditional immunosuppressive therapy, RTX treatment can effectively induce clinically complete remission or partial remission with good safety.