Delayed but durable remission to rituximab in PLA2R-associated membranous nephropathy despite B-cell reconstitution: a case report

作者：rushuang Yang, Hongjie Zhu, Ziyan Luo, Tingting He, Mei Jiang, Yanling Zhang, Ting Wang · 发表于：BMC Nephrology · 年份：2026 · DOI：10.1186/s12882-026-04830-3 · 研究领域：Renal Diseases and Glomerulopathies、Amyloidosis: Diagnosis, Treatment, Outcomes、Complement system in diseases

Rituximab (RTX) is widely used as first-line therapy for PLA2R-associated membranous nephropathy (MN), but the optimal timing for assessing response and guiding retreatment remains uncertain, particularly in patients with slow clinical improvement. We report a 46-year-old man with PLA 2 R-associated MN who showed poor response to high-dose glucocorticoids and was subsequently treated with a low-dose, fractionated RTX regimen (total 3.6 g over 14 months).Notably, a significant reduction in proteinuria was not observed until 19 months after treatment initiation, when partial remission (proteinuria < 3.5 g/day) was first achieved. During 44 months of follow-up, proteinuria continued to decline and remission was maintained, while anti-PLA 2 R antibodies remained negative despite gradual reconstitution of circulating CD19⁺ B cells, and no further immunosuppressive therapy was administered.This case demonstrates a markedly delayed but durable clinical response to rituximab and illustrates that B-cell repopulation does not necessarily indicate disease relapse when anti-PLA 2 R antibodies remain suppressed, supporting the value of antibody-guided rather than B-cell-guided monitoring in slow responders.