Li Ai-Hui, Li Yang, Li Meng-Shi, Song Zhuo-Ran, Lv Ji-Cheng, Zhang Hong, Yu Xiao-Juan, Zhou Xu-Jie
Renal Division, Peking University First Hospital, Beijing, China.
Kidney Genetics Center, Peking University Institute of Nephrology, Beijing, China.
Kidney Dis (Basel). 2025 Apr 4;11(1):258-269. doi: 10.1159/000545727. eCollection 2025 Jan-Dec.
Membranoproliferative glomerulonephritis (MPGN) is a heterogeneous pattern of glomerular injury. Repeated kidney biopsies may elucidate pathogenic mechanisms and guide diagnostic strategies.
We included 82 patients diagnosed with MPGN by kidney biopsy who underwent at least two biopsies between 1997 and 2023 at Peking University First Hospital. Clinical and pathological data were analyzed retrospectively.
Of 342 MPGN patients, 95 (28%) had repeated biopsies (0.9-4.0 years apart). This incidence was higher than in other glomerulonephropathies under immunosuppression. Among the 82 patients analyzed (excluding kidney transplants and ≤3-month biopsy intervals), 42 were initially diagnosed with non-MPGN pathology. At the second biopsy, proteinuria increased (from 2.9 to 6.3 g/day), eGFR declined (from 76 to 47 mL/min/1.73 m), and renal C3 deposition was stronger ( = 0.04). Thirty patients (37%) had etiological reclassification, mostly to monoclonal gammopathy of renal significance (MGRS). Compared to idiopathic MPGN, MGRS patients were older (53 vs. 35 years) and had worse renal function (eGFR 57 vs. 81 mL/min/1.73 m) but slower eGFR decline (-7 vs. -12 mL/min/1.73 m/year). Most MGRS patients (64%) remained negative for monoclonal protein in serum or urine immunofixation, necessitating repeat biopsy and clone-directed therapy.
In this study, about half and one-third of patients underwent morphological and etiological reclassification, respectively. Stronger complement deposition may drive morphological changes. Repeated kidney biopsies are crucial for diagnosing MGRS, especially in patients with negative immunofixation.
膜增生性肾小球肾炎（MPGN）是一种肾小球损伤的异质性模式。重复肾活检可能有助于阐明致病机制并指导诊断策略。
我们纳入了82例经肾活检诊断为MPGN的患者，这些患者于1997年至2023年期间在北京医科大学第一医院接受了至少两次活检。对临床和病理数据进行回顾性分析。
在342例MPGN患者中，95例（28%）进行了重复活检（间隔时间为0.9至4.0年）。这一发生率高于其他接受免疫抑制治疗的肾小球疾病。在分析的82例患者中（不包括肾移植患者和活检间隔≤3个月的患者），42例最初被诊断为非MPGN病理类型。在第二次活检时，蛋白尿增加（从2.9克/天增至6.3克/天），估算肾小球滤过率（eGFR）下降（从76降至47毫升/分钟/1.73平方米），肾C3沉积更强（P = 0.04）。30例患者（37%）进行了病因重新分类，大多重新分类为具有肾脏意义的单克隆丙种球蛋白病（MGRS）。与特发性MPGN相比，MGRS患者年龄更大（53岁对35岁），肾功能更差（eGFR分别为57和81毫升/分钟/1.73平方米），但eGFR下降速度较慢（-7对-12毫升/分钟/1.73平方米/年）。大多数MGRS患者（64%）血清或尿免疫固定电泳中的单克隆蛋白仍为阴性，需要重复活检和针对克隆的治疗。
在本研究中，分别约有一半和三分之一的患者进行了形态学和病因学重新分类。更强的补体沉积可能推动形态学变化。重复肾活检对于诊断MGRS至关重要，尤其是在免疫固定电泳阴性的患者中。
