蛋白尿已被确定为ANCA相关性肾小球肾炎患者肾脏结局的预测因子。但这些患者的蛋白尿是否与足细胞异常有关,目前尚不清楚。我们在这里调查了25例与蛋白尿有关的ANCA相关性肾小球肾炎的白种人患者的诊断性肾活检中足细胞足过程宽度和足细胞标记WT-1阳性的足细胞数量。使用来自移植前供体肾活检的对照组织。随访10周时的蛋白尿与足突宽度显着相关(P=0.04)。足突宽度≥600nm的活检更多属于新月形或混合类,而足突宽度<600nm的活检最常归类为局灶性类别(P=0.03).与对照组相比,患者基于WT-1表达的足细胞平均数量显着降低(15vs.每个肾小球34只足细胞;P<0.0001)。在ANCA相关的肾小球肾炎中足细胞WT-1标记物的表达的显著降低被认为是实际足细胞损失的指示或至少,功能的丧失。此外,我们的研究表明,基线足细胞足突宽度可能是短期随访时蛋白尿的指标。出于预后目的,因此,我们建议在ANCA相关性肾小球肾炎活检的诊断报告中包括足突宽度的描述.
Proteinuria has been identified as prognosticator of renal outcome in patients with ANCA-associated glomerulonephritis, but whether proteinuria is related to
podocyte abnormalities in these patients is largely unknown. We here investigate
podocyte foot process width and number of podocytes positive for the
podocyte marker WT-1 in diagnostic renal biopsies of 25 Caucasian patients with ANCA-associated glomerulonephritis in relation to proteinuria. Control tissue was used from pre-transplantation donor kidney biopsies. Proteinuria at 10 weeks follow-up correlated significantly with foot process width (P = 0.04). Biopsies with foot process width ≥600 nm belonged more often to the crescentic or mixed class, whereas biopsies with a foot process width <600 nm were most often categorized as focal class (P = 0.03). The mean number of podocytes based upon expression of WT-1 was significantly lower in patients compared to controls (15 vs. 34 podocytes per glomerulus; P < 0.0001). The significant decrease in expression of the
podocyte WT-1 marker in ANCA-associated glomerulonephritis is considered indicative of actual
podocyte loss or at least, of a loss of functionality. Furthermore, our study indicates that
podocyte foot process width at baseline could be indicative for proteinuria at short term follow up. For prognostic purposes, we therefore suggest to include a description of the foot process width in the diagnostic report of a biopsy with ANCA-associated glomerulonephritis.