Hakroush Samy, Kluge Ingmar Alexander, Ströbel Philipp, Korsten Peter, Tampe Désirée, Tampe Björn
Institute of Pathology, University Medical Center Göttingen, 37075 Göttingen, Germany.
Department of Nephrology and Rheumatology, University Medical Center Göttingen, 37075 Göttingen, Germany.
J Clin Med. 2021 Mar 16;10(6):1231. doi: 10.3390/jcm10061231.
Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a systemic vasculitis, most frequently presenting as microscopic polyangiitis (MPA) or granulomatosis with polyangiitis (GPA). Kidney involvement is a common and severe complication of ANCA AAV which is observed in a considerable subset of patients, mainly affecting glomeruli. However, tubulointerstitial lesions have also been described in ANCA glomerulonephritis (GN). Therefore, we aim to describe active and chronic tubulointerstitial lesions in ANCA GN subtypes by systematic scoring analogous to the Banff scoring system while also utilizing clinical and laboratory findings.
A total of 49 kidney biopsies with ANCA GN were retrospectively included in a single-center cohort study between 2015-2020.
We report that MPO-ANCA GN is associated with more severe deterioration of kidney function independent of systemic markers of AAV disease activity, and is also associated with increased proteinuria in MPO-ANCA GN and a decreased fraction of normal glomeruli. Finally, MPO-ANCA GN showed distinct, active, and chronic tubulointerstitial lesions.
New insights into the pathophysiology of both entities, as well as differences in the clinical presentation of MPO- versus PR3-ANCA GN, could potentially pave the way for more precise treatment regimens. Therefore, it is important to understand the differences in histopathological presentation, especially in yet underestimated active tubulointerstitial lesions of ANCA GN subtypes. This research could further improve our understanding of distinct pathophysiological mechanisms.
抗中性粒细胞胞浆抗体（ANCA）相关血管炎（AAV）是一种系统性血管炎，最常见的表现形式为显微镜下多血管炎（MPA）或肉芽肿性多血管炎（GPA）。肾脏受累是ANCA相关性AAV常见且严重的并发症，在相当一部分患者中可见，主要影响肾小球。然而，在ANCA相关性肾小球肾炎（GN）中也有肾小管间质病变的描述。因此，我们旨在通过类似于班夫评分系统的系统评分来描述ANCA相关性GN亚型中的活动性和慢性肾小管间质病变，同时利用临床和实验室检查结果。
2015年至2020年期间，一项单中心队列研究回顾性纳入了49例经肾活检确诊为ANCA相关性GN的患者。
我们报告，MPO-ANCA相关性GN与更严重的肾功能恶化相关，这与AAV疾病活动的全身标志物无关，并且在MPO-ANCA相关性GN中还与蛋白尿增加以及正常肾小球比例降低有关。最后，MPO-ANCA相关性GN表现出独特的、活动性和慢性肾小管间质病变。
对这两种疾病病理生理学的新认识，以及MPO-与PR3-ANCA相关性GN临床表现的差异，可能为更精确的治疗方案铺平道路。因此，了解组织病理学表现的差异很重要，尤其是在ANCA相关性GN亚型中尚未得到充分重视的活动性肾小管间质病变方面。这项研究可以进一步增进我们对不同病理生理机制的理解。
