Department of Nephrology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080, China.
Key Laboratory of Nephrology, National Health Commission and Guangdong Province, Guangzhou, 510080, China.
Clin Exp Med. 2022 Aug;22(3):455-464. doi: 10.1007/s10238-021-00768-y. Epub 2021 Oct 26.
Glomerular IgM deposition is commonly shown in idiopathic membranous nephropathy, but the clinicopathological features and outcomes of IMN with IgM deposition are unclear. This single-center prospective cohort study enrolled 210 patients with biopsy-proven IMN from January 2016 to December 2018. Clinicopathological features, treatment responses, and kidney outcomes were compared between patients with and without IgM deposition. In total, 76 (36.2%) patients show glomerular IgM deposition. Patients with IgM deposition were younger (45 ± 13.30 vs. 50.59 ± 13.65 years, P = 0.006), had a higher estimated glomerular filtration rate (eGFR) (100.03 [81.31-111.37] vs. 92.67 [74.71-106.63] mL/min/1.73 m, P = 0.041), and had a lower proportion of nephrotic syndrome (60.5% vs. 75.4%, P = 0.024) at the time of kidney biopsy. Patients with IgM deposition had a significantly higher proportion of focal segmental glomerular sclerosis (FSGS) lesions (27.6% vs. 13.4%, P = 0.011) and C1q deposition (72.4% vs. 57.5%, P = 0.032). Although the treatments and initial treatment responses were comparable, patients with glomerular IgM deposition had a significantly greater proportion of eGFR decline of ≥ 5 mL/min/1.73 m per year (log-rank test, P < 0.001) and eGFR decrease of ≥ 10% from baseline (log-rank test, P = 0.003). Cox regression analysis showed that IgM deposition was an independent risk factor of eGFR decline of ≥ 5 mL/min/1.73 m per year (HR, 2.442; 95% CI, 1.550-3.848, P < 0.001) and eGFR decline by ≥ 10% from baseline (HR, 2.629; 95% CI, 1.578-4.385, P < 0.001) during follow-up. IgM deposition in the glomeruli is an independent risk factor for decreased renal function in patients with IMN.
肾小球 IgM 沉积在特发性膜性肾病中较为常见，但 IgM 沉积的特发性膜性肾病的临床病理特征和结局尚不清楚。本单中心前瞻性队列研究纳入了 2016 年 1 月至 2018 年 12 月期间经活检证实的 210 例特发性膜性肾病患者。比较了有和无 IgM 沉积的患者的临床病理特征、治疗反应和肾脏结局。共有 76 例（36.2%）患者出现肾小球 IgM 沉积。有 IgM 沉积的患者更年轻（45±13.30 岁 vs. 50.59±13.65 岁，P=0.006），估算肾小球滤过率（eGFR）更高（100.03[81.31-111.37] vs. 92.67[74.71-106.63] mL/min/1.73 m，P=0.041），且在肾活检时肾病综合征的比例更低（60.5% vs. 75.4%，P=0.024）。有 IgM 沉积的患者局灶节段性肾小球硬化（FSGS）病变的比例明显更高（27.6% vs. 13.4%，P=0.011）和 C1q 沉积的比例更高（72.4% vs. 57.5%，P=0.032）。尽管治疗和初始治疗反应相当，但有肾小球 IgM 沉积的患者 eGFR 每年下降≥5 mL/min/1.73 m 的比例明显更高（对数秩检验，P<0.001），且 eGFR 较基线下降≥10%的比例也更高（对数秩检验，P=0.003）。Cox 回归分析显示，IgM 沉积是 eGFR 每年下降≥5 mL/min/1.73 m（HR，2.442；95%CI，1.550-3.848，P<0.001）和 eGFR 较基线下降≥10%（HR，2.629；95%CI，1.578-4.385，P<0.001）的独立危险因素。肾小球内 IgM 沉积是特发性膜性肾病患者肾功能下降的独立危险因素。
