Hospital Universitário Antônio Pedro, Universidade Federal Fluminense, Niterói, RJ, Brasil.
Braz J Med Biol Res. 2020;53(6):e8625. doi: 10.1590/1414-431x20208625. Epub 2020 May 18.
Amyloidosis comprises a group of disorders that accumulate modified autologous proteins in organs, mainly the kidneys. Few studies have addressed the amyloid compartmental distribution and associated clinical outcomes. The aim of this study was to present a case series of renal amyloidosis correlating histopathological data with glomerular filtration rate (GFR) during kidney biopsy. We studied 53 cases reviewed by nephropathologists from 2000 to 2018 in a single kidney biopsy center in Brazil. GFR was estimated using the CKD-EPI formula. Cases were divided into Group A ≥60 and Group B <60 mL·min-1·(1.73 m2)-1 using the estimated GFR during kidney biopsy. Semiquantitative histopathological study was performed, including extension and distribution of amyloid deposits by compartments (glomeruli, tubulointerstitial tissue, and vessels). Statistical analyses were made to understand associations with lower GFR. No difference was seen for age, gender, proteinuria, hematuria, subtype of amyloid protein, arteriosclerosis, interstitial fibrosis/infiltrate, or glomerular and interstitial amyloid deposits. After a previous P value <0.1 in the descriptive analysis, the following variables were selected: globally sclerotic glomeruli, high blood pressure, and the extension of vascular amyloid deposition. A binary logistic regression model with GFR as the dependent variable showed history of hypertension and vascular amyloid to be robust and independent predictors of Group B <60 mL·min-1·(1.73 m2)-1. Beyond the histopathologic diagnosis of amyloidosis, a semiquantitative approach on renal biopsy could provide new insights. Vascular amyloid is an independent predictor of renal dysfunction in cases of renal amyloidosis.
淀粉样变性症包括一组在器官中积累修饰后的自体蛋白的疾病，主要累及肾脏。少数研究涉及淀粉样物质的隔室分布及其相关的临床结局。本研究旨在通过肾活检时的组织病理学数据与肾小球滤过率（GFR）的相关性，呈现一组肾淀粉样变性症的病例系列。我们研究了 2000 年至 2018 年期间在巴西一个单中心肾活检中心由肾脏病学家回顾的 53 例病例。使用 CKD-EPI 公式估计 GFR。根据肾活检时估计的 GFR 将病例分为 GFR≥60 mL·min-1·(1.73 m2)-1 组（Group A）和 GFR＜60 mL·min-1·(1.73 m2)-1 组（Group B）。进行了半定量组织病理学研究，包括通过隔室（肾小球、肾小管间质组织和血管）评估淀粉样物质沉积的扩展和分布。进行了统计学分析以了解与较低 GFR 的相关性。年龄、性别、蛋白尿、血尿、淀粉样蛋白亚型、动脉硬化、间质纤维化/浸润、肾小球和间质淀粉样物质沉积在两组间均无差异。在描述性分析中 P 值＜0.1 的变量被筛选出来，随后进行二元逻辑回归模型分析，以 GFR 为因变量。结果显示，全球硬化性肾小球、高血压和血管淀粉样物质沉积的扩展是 GFR＜60 mL·min-1·(1.73 m2)-1 的独立预测因素。除了淀粉样变性症的组织病理学诊断外，肾活检的半定量方法还可以提供新的见解。血管淀粉样物质是肾淀粉样变性症患者肾功能障碍的独立预测因素。
