Dept. of Laboratory Medicine, Basel University Hospital, Petersgraben 4, CH 4031 Basel, Switzerland.
Eur J Intern Med. 2009 Oct;20(6):556-61. doi: 10.1016/j.ejim.2009.03.006. Epub 2009 Apr 10.
Chronic kidney disease is often not associated with significant symptoms or abnormalities in common laboratory test results. Diagnosis is supposedly facilitated by calculating the glomerular filtration rate (GFR) from serum creatinine. A reference range GFR, however, does not exclude renal disease, because renal disease causes the subsequent decrease of renal function. Thorough analysis of proteinuria, however, requires a profound knowledge of the renal handling of the different marker proteins of glomerular and tubular origin. This paper summarizes the scientific basis, explains the diagnostic rationale and proves the concept by analyzing 5669 samples, where GFR and proteinuria work-up were available. 63% (1446 of 2287) of the samples with a GFR above 60 showed either glomerular (37.8%, n=865) or tubular proteinuria (25.4%, n= 581). The quantity of proteinuria increased severely with decreasing kidney function. The rate of glomerular proteinuria remained nearly constant in the different GFR groups, while primarily tubular proteinuria increased from 23% to 63%. A proteinuria pattern indicating a good response to therapy was frequently combined with a high GFR (selective glomerular proteinuria/ incomplete tubular proteinuria), while the severe forms of unselective or complete tubular proteinuria associated with a severe GFR decrease. Regression analysis showed a better inverse correlation of GFR with tubular (r=-0.643) than glomerular markers (r=-0.360; combined r=-0.646). We believe that this complex interrelated laboratory information must be delivered most effectively, i.e. with the use of a knowledge based system in combination with improved, visual oriented laboratory output.
慢性肾病通常不会出现明显的症状或常见实验室检查结果异常。通过计算血清肌酐来估算肾小球滤过率（GFR），有助于诊断。然而，参考范围的 GFR 并不能排除肾脏疾病，因为肾脏疾病会导致随后的肾功能下降。然而，要彻底分析蛋白尿，需要深入了解肾脏对肾小球和肾小管来源的不同标志物蛋白的处理。本文通过分析 5669 份同时具有 GFR 和蛋白尿检测结果的样本，总结了科学依据，解释了诊断原理，并通过验证概念。在 GFR 大于 60 的 1446 份样本（2287 份中的 63%）中，无论是肾小球性（37.8%，n=865）还是肾小管性蛋白尿（25.4%，n=581）都存在。随着肾功能下降，蛋白尿的量会严重增加。肾小球性蛋白尿的比例在不同 GFR 组中几乎保持不变，而主要是肾小管性蛋白尿从 23%增加到 63%。一种预示治疗效果良好的蛋白尿模式通常与高 GFR 相关（选择性肾小球性蛋白尿/不完全肾小管性蛋白尿），而与严重 GFR 下降相关的严重非选择性或完全肾小管性蛋白尿则提示预后不良。回归分析显示 GFR 与肾小管标志物的相关性更好（r=-0.643），而与肾小球标志物的相关性稍差（r=-0.360；综合 r=-0.646）。我们认为，这种复杂的实验室信息必须以最有效的方式传递，即使用基于知识的系统结合改进的、面向视觉的实验室输出。
