Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey,
Division of Nephrology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey.
Kidney Blood Press Res. 2019;44(5):961-972. doi: 10.1159/000501827. Epub 2019 Aug 22.
BACKGROUND/AIMS: We aimed to investigate the effects of glomerular IgM and C3 deposition on outcomes of adult patients with primary focal segmental glomerulosclerosis (FSGS).
In this retrospective analysis, 86 consecutive adult patients with biopsy-proven primary FSGS were stratified into 3 groups according to their histopathological features: IgM- C3-, IgM+ C3-, and IgM+ C3+. Primary outcome was defined as at least a 50% reduction in baseline estimated glomerular filtration rate (eGFR) or development of kidney failure, while complete or partial remission rates were secondary outcomes.
Glomerular IgM deposits were found in 44 (51.1%) patients, 22 (25.5%) of which presented with accompanying C3 deposition. Patients in IgM+ C3+ group had higher level of proteinuria (5.6 g/24 h [3.77-8.5], p = 0.073), higher percentage of segmental glomerulosclerosis (20% [12.3-27.2], p = 0.001), and lower levels of eGFR (69 ± 37.2 mL/min/1.73 m2, p = 0.029) and serum albumin (2.71 ± 0.85 g/dL, p = 0.045) at the time of diagnosis. Despite 86.3% of patients in IgM+ C3+ group (19/22) received immunosuppressive treatment, the primary outcome was more common in patients in the IgM+ C3+ group compared with patients in IgM+ C3- and IgM- C3- groups (11 [50%] vs. 2 [9%] and 11 [26.1%] respectively [p = 0.010]). Complete or partial remission rates were lower in patients in the IgM+ C3+ group (5/22, 22.7%), as well (p = 0.043). Multivariate Cox regression analysis revealed that IgM and C3 co-deposition was an independent risk factor associated with primary outcome (hazard ratio 3.355, 95% CI 1.349-8.344, p = 0.009).
Glomerular IgM and C3 co-deposition is a predictor of unfavorable renal outcomes in adult patients with primary FSGS.
背景/目的：本研究旨在探讨肾小球 IgM 和 C3 沉积对原发性局灶节段性肾小球硬化症（FSGS）成年患者结局的影响。
在这项回顾性分析中，根据组织病理学特征将 86 例经活检证实的原发性 FSGS 成年患者分为 3 组：IgM-C3-、IgM+C3-和 IgM+C3+。主要结局定义为基线估计肾小球滤过率（eGFR）下降至少 50%或发生肾功能衰竭，完全或部分缓解率为次要结局。
44 例（51.1%）患者存在肾小球 IgM 沉积，其中 22 例（25.5%）伴有 C3 沉积。IgM+C3+组患者蛋白尿水平更高（5.6 g/24 h [3.77-8.5]，p = 0.073），节段性肾小球硬化比例更高（20% [12.3-27.2]，p = 0.001），eGFR 水平更低（69 ± 37.2 mL/min/1.73 m2，p = 0.029）和血清白蛋白水平更低（2.71 ± 0.85 g/dL，p = 0.045）。尽管 86.3%（19/22）的 IgM+C3+组患者接受了免疫抑制治疗，但与 IgM+C3-和 IgM-C3-组患者相比，IgM+C3+组患者的主要结局更为常见（11 例[50%]比 2 例[9%]和 11 例[26.1%]，p = 0.010）。IgM+C3+组患者的完全或部分缓解率也较低（5/22，22.7%，p = 0.043）。多变量 Cox 回归分析显示，IgM 和 C3 共沉积是与原发性 FSGS 成年患者主要结局相关的独立危险因素（风险比 3.355，95%CI 1.349-8.344，p = 0.009）。
肾小球 IgM 和 C3 共沉积是原发性 FSGS 成年患者不良肾脏结局的预测因子。
