Department of Nephrology and Rheumatology, University Medical Center Göttingen, Göttingen, Germany.
Institute of Pathology, University Medical Center Göttingen, Göttingen, Germany.
J Nephrol. 2023 Apr;36(3):799-808. doi: 10.1007/s40620-022-01486-8. Epub 2022 Dec 21.
Renal involvement is a common and severe complication of anti-neutrophil cytoplasmic antibody-(ANCA)-associated vasculitis potentially resulting in pauci-immune necrotizing and crescentic ANCA glomerulonephritis (GN) with rapid deterioration of kidney function, progression to end stage kidney disease or, if left untreated, lethal exitus. Analysis of the urinary sediment routinely supports clinical management of ANCA GN, but histopathological implications of aberrancies in the urinary sediment mostly remain elusive. Therefore, we aimed to systematically assess the correlation of aberrancies in the urinary sediment and clinico-pathologic findings.
A total of 42 kidney biopsies with ANCA GN were retrospectively analyzed in a single-center observational study. Laboratory and histopathological parameters were systematically analyzed and correlated with findings of the urinary sediment.
In the overall ANCA GN cohort, leukocyturia and hematuria were associated among each other, and with markers for non-selective glomerular damage, respectively. Non-invasive measurement of leukocyturia indicated focal (but not extensive) Bowman's capsule rupture (BCR) specifically in proteinase-3 (PR3)-ANCA GN, whereas hematuria correlated with extensive (but not focal) BCR. Concerning intrarenal immune cell infiltration, leukocyturia was associated with tubulointerstitial plasma cell infiltration in PR3-ANCA GN. Finally, none of these associations were detectable in myeloperoxidase-ANCA GN, implying different modes of kidney damage.
We herein expand our current knowledge by providing evidence that leukocyturia and hematuria enable non-invasive differentiation of BCR severity specifically in PR3-ANCA GN.
肾损伤是抗中性粒细胞胞浆抗体（ANCA）相关性血管炎的常见且严重的并发症，可能导致少免疫性坏死性新月体性 ANCA 肾小球肾炎（GN），使肾功能迅速恶化，进展为终末期肾病，或者如果不治疗，则导致死亡。尿液沉淀物分析常规支持 ANCA GN 的临床管理，但尿液沉淀物中异常的组织病理学意义大多仍不清楚。因此，我们旨在系统评估尿液沉淀物异常与临床病理发现之间的相关性。
在一项单中心观察性研究中，回顾性分析了总共 42 例 ANCA GN 肾活检。系统分析了实验室和组织病理学参数，并与尿液沉淀物的发现进行了相关性分析。
在整体 ANCA GN 队列中，白细胞尿和血尿相互关联，分别与非选择性肾小球损伤标志物相关。白细胞尿的非侵入性测量特别表明蛋白酶 3（PR3）-ANCA GN 中存在局灶性（而非广泛性）Bowman 囊破裂（BCR），而血尿与广泛（而非局灶性）BCR 相关。关于肾内免疫细胞浸润，白细胞尿与 PR3-ANCA GN 中的肾小管间质浆细胞浸润相关。最后，在髓过氧化物酶-ANCA GN 中未检测到这些关联，表明存在不同的肾损伤模式。
我们通过提供证据表明，白细胞尿和血尿能够在 PR3-ANCA GN 中特异性地对 BCR 严重程度进行非侵入性区分，从而扩展了我们目前的知识。
