Abstract

Glomerular filtration rate (GFR) measured by urinary clearance of inulin is considered the gold standard for assessment of kidney function in both adults and children. Because the procedure is cumbersome, GFR is estimated (eGFR) using algorithms based on the observed relationship between measured GFR (mGFR) and more accessible biomarkers such as creatinine and cystatin C. In children, most of the data on this relationship is retrieved from patients with reduced kidney function. Nonetheless, eGFR equations are widely in use in healthy children to evaluate kidney status and diagnose kidney disease. The aim of the present study was to compare the distribution of eGFR using two established pediatric eGFR equations incorporating age, height and serum creatinine (Schwartz-Lyon and Full Age Spectrum-height) and two recently published equations restricted to age and serum creatinine (Lund-Malmö Revised 18 and European Kidney Function Consortium equation) in 1200 healthy schoolchildren age 6–12 years. In addition, we present 2.5^th, median and 97.5^th percentiles for serum creatinine stratified by age and gender. Depending on the equation used, mean eGFR ranged from 101.6 to 115.4 mL/min/1.73 m². The lower 2.5^th percentile ranged from 83.3 to 89.0 mL/min/1.73 m² and the fraction of children with eGFR < 90 mL/min/1.73 m² ranged from 2.9% to 9.8%. In conclusion, expected values of eGFR in healthy children are significantly dependent on the equation used. When decision limits for diagnosis or classification are applied to eGFR results, the related equation should be clearly stated.

摘要

通过菊粉的尿清除率测量的肾小球滤过率 (GFR) 被认为是评估成人和儿童肾功能的金标准。由于该过程繁琐，因此使用基于测量的 GFR (mGFR) 与更容易获得的生物标志物（例如肌酐和胱抑素 C随着肾功能下降。尽管如此，eGFR 方程在健康儿童中被广泛用于评估肾脏状况和诊断肾脏疾病。本研究的目的是使用两个已建立的结合年龄的儿科 eGFR 方程来比较 eGFR 的分布，身高和血清肌酐（Schwartz-Lyon 和 Full Age Spectrum-height）以及最近发表的两个针对年龄和血清肌酐的方程（Lund-Malmö 修订版 18 和欧洲肾功能协会方程），针对 1200 名 6-12 岁的健康学童。此外，我们提出 2.5按年龄和性别分层的血清肌酐的^th、中位数和 97.5 ^{th百分位数。}根据所使用的公式，平均 eGFR 范围为 101.6 至 115.4 mL/min/1.73 m ²。较低的第 2.5^个百分位数范围为 83.3 至 89.0 mL/min/1.73 m ^{2 ，而 eGFR < 90 mL/min/1.73 m 2}的儿童比例范围为 2.9% 至 9.8%。总之，健康儿童的 eGFR 预期值在很大程度上取决于所使用的方程。当诊断或分类的决策限应用于 eGFR 结果时，应明确说明相关方程。