da Luz Neto Epitácio Rafael, Tavares Maria Brandão, de Melo Ana Gabriela de Jesus Torres, Dos-Santos Washington L C, Malheiros Denise Maria Avancini Costa, Yu Luís
Division of Nephrology, Hospital das Clínicas, University of São Paulo School of Medicine, São Paulo 05403-010, SP, Brazil.
Hospital Ana Nery, Salvador 40320-010, BA, Brazil.
Diagnostics (Basel). 2024 Nov 27;14(23):2681. doi: 10.3390/diagnostics14232681.
Since the introduction of the SLICC criteria in 2012, biopsy-proven lupus nephritis (LN) has been the only independent diagnostic criterion for systemic lupus erythematosus (SLE). This was reaffirmed by the EULAR/ACR in 2019, emphasizing the importance of renal biopsy in LN. However, the current classification lacks specific histopathological criteria for defining LN. This study describes the histological findings of patients with LN, compares them with those of other glomerular diseases, and evaluates their diagnostic accuracy in a large Latin American population.
This retrospective cohort included 731 kidney biopsies from two distinct academic centers. The patients were divided into two groups as follows: a LN group and a control group comprising patients with membranous nephropathy, IgA nephropathy, membranoproliferative glomerulonephritis, pauci-immune glomerulonephritis, and proliferative glomerulonephritis. Sensitivity and specificity analyses were conducted for various histopathological features.
We identified the following five features strongly correlated with LN: mesangial proliferation, subendothelial deposits, C1q staining ≥1+, dominant IgG, and ≥4 positive immunofluorescence elements. Combined, these features yielded an area under the ROC curve of 0.94 (95% CI: 0.91-0.95). These results were validated in a diverse population. In membranous nephropathy, histological features such as mesangial deposits, C1q positivity, and ≥4 positive immunofluorescence elements effectively distinguished class V LN from non-lupus membranous nephropathy, with an area under the ROC curve of 0.85 (95% CI: 0.76-0.93).
The combination of mesangial proliferation, subendothelial deposits, C1q staining ≥1+, dominant IgG, and ≥4 positive immunofluorescence elements offer good accuracy for diagnosing renal involvement in SLE in a large Latin American population. In the absence of pathognomonic features, combined criteria are valuable diagnostic tools, particularly when other SLE criteria are lacking.
自2012年引入SLICC标准以来，经活检证实的狼疮性肾炎（LN）一直是系统性红斑狼疮（SLE）唯一的独立诊断标准。2019年欧洲抗风湿病联盟（EULAR）/美国风湿病学会（ACR）再次确认了这一点，强调了肾活检在LN中的重要性。然而，目前的分类缺乏定义LN的具体组织病理学标准。本研究描述了LN患者的组织学发现，将其与其他肾小球疾病的发现进行比较，并在拉丁美洲的一大群人中评估其诊断准确性。
这项回顾性队列研究纳入了来自两个不同学术中心的731例肾活检病例。患者分为两组：LN组和对照组，对照组包括膜性肾病、IgA肾病、膜增生性肾小球肾炎、寡免疫性肾小球肾炎和增生性肾小球肾炎患者。对各种组织病理学特征进行了敏感性和特异性分析。
我们确定了与LN密切相关的以下五个特征：系膜增生、内皮下沉积物、C1q染色≥1+、主要为IgG以及≥4个阳性免疫荧光成分。综合这些特征，ROC曲线下面积为0.94（95%CI：0.91-0.95）。这些结果在不同人群中得到了验证。在膜性肾病中，系膜沉积物、C1q阳性以及≥4个阳性免疫荧光成分等组织学特征有效地将Ⅴ类LN与非狼疮性膜性肾病区分开来，ROC曲线下面积为0.85（95%CI：0.76-0.93）。
系膜增生、内皮下沉积物、C1q染色≥1+、主要为IgG以及≥4个阳性免疫荧光成分的组合，对于在拉丁美洲一大群人中诊断SLE的肾脏受累具有良好的准确性。在缺乏特征性表现的情况下，联合标准是有价值的诊断工具，特别是在缺乏其他SLE标准时。
