评估基于白蛋白的蛋白尿选择性指数作为基于转铁蛋白的蛋白尿选择性指数的替代指标。
Evaluation of albumin-based proteinuria selectivity index as a substitute for transferrin-based proteinuria selectivity index.
作者信息
Kukida Masayoshi, Kinnami Shingo, Takasuka Yasunori, Kondo Fumikazu, Shichijo Satoru, Morita Yohei, Miyoshi Ken-Ichi, Yamaguchi Osamu
机构信息
Department of Cardiology, Pulmonology, Hypertension and Nephrology, Ehime University Graduate School of Medicine, Toon, Ehime, 7910295, Japan.
Department of Clinical Laboratory, Ehime University Hospital, Toon, Ehime, 7910295, Japan.
出版信息
Clin Exp Nephrol. 2025 Aug 26. doi: 10.1007/s10157-025-02753-1.
BACKGROUND
The proteinuria selectivity index (SI) is a valuable marker of glomerular permeability. Traditionally, SI has been calculated using the clearance ratio of immunoglobulin G (IgG) to transferrin-SI (Tf)-due to historical limitations in albumin measurement accuracy. However, recent advances have enabled precise quantification of albumin, raising the possibility of using an albumin-based SI-SI (Alb)-in clinical practice. This study aimed to evaluate the correlation between SI (Alb) and SI (Tf) and to compare their diagnostic utility in patients with proteinuria.
METHODS
We retrospectively analyzed 265 patients with proteinuria > 0.15 g/g·Cr who visited Ehime University Hospital between January 2014 and April 2024. SI (Alb) and SI (Tf) were calculated as the clearance ratios of IgG to albumin and IgG to transferrin, respectively. Linear regression was used to assess their correlation. Diagnostic performance for minimal change disease (MCD) in patients with nephrotic-range proteinuria (≥ 3.5 g/g·Cr) was evaluated using ROC curves, and AUCs were compared using DeLong's test.
RESULTS
SI (Alb) strongly correlated with SI (Tf) in patients with proteinuria ≥ 3.5 and < 3.5 g/g·Cr. Among patients with nephrotic-range proteinuria, both indices effectively identified MCD, yielding comparable areas under the ROC curve. Sensitivity and specificity at optimal thresholds were similarly high.
CONCLUSION
SI (Alb) shows a high degree of concordance with SI (Tf) and offers comparable diagnostic accuracy for identifying MCD. Given its practical advantages, SI (Alb) may serve as a reliable and convenient alternative to SI (Tf) for assessing glomerular selectivity in patients with proteinuria.
背景
蛋白尿选择性指数（SI）是肾小球通透性的一个重要标志物。传统上，由于白蛋白测量准确性方面的历史局限性，SI一直通过免疫球蛋白G（IgG）与转铁蛋白-SI（Tf）的清除率来计算。然而，最近的进展使得白蛋白能够被精确量化，从而提高了在临床实践中使用基于白蛋白的SI即SI（Alb）的可能性。本研究旨在评估SI（Alb）与SI（Tf）之间的相关性，并比较它们在蛋白尿患者中的诊断效用。
方法
我们回顾性分析了2014年1月至2024年4月期间就诊于爱媛大学医院的265例蛋白尿>0.15 g/g·Cr的患者。SI（Alb）和SI（Tf）分别计算为IgG与白蛋白以及IgG与转铁蛋白的清除率。采用线性回归评估它们的相关性。使用ROC曲线评估肾病范围蛋白尿（≥3.5 g/g·Cr）患者中微小病变病（MCD）的诊断性能，并使用德龙检验比较曲线下面积（AUC）。
结果
在蛋白尿≥3.5和<3.5 g/g·Cr的患者中，SI（Alb）与SI（Tf）密切相关。在肾病范围蛋白尿患者中，这两个指标都能有效地识别MCD，ROC曲线下面积相当。最佳阈值时的敏感性和特异性同样很高。
结论
SI（Alb）与SI（Tf）高度一致，在识别MCD方面具有相当的诊断准确性。鉴于其实际优势，SI（Alb）可能是评估蛋白尿患者肾小球选择性的一种可靠且便捷的替代指标，可替代SI（Tf）。
Zotero 插件