Department of Pediatrics, VU University Medical Center, Amsterdam, The Netherlands.
Department of Pediatric Nephrology, VU University Medical Center, De Boelelaan 1118, NL-1081 HV, Amsterdam, The Netherlands.
Pediatr Nephrol. 2018 Sep;33(9):1553-1563. doi: 10.1007/s00467-018-3973-8. Epub 2018 May 17.
Combining estimated glomerular filtration rate (eGFR) equations based on creatinine and cystatin C has been shown to improve the accuracy of GFR estimation. This study aims to optimize this strategy for height-independent GFR estimation in children.
Retrospective study of 408 inulin clearance tests with simultaneous International Federation of Clinical Chemistry-calibrated measurements of creatinine, cystatin C, and urea in children (mean age 12.5 years, GFR 91.2 ml/min/1.73m) comparing the arithmetic (mean) and geometric means (mean) of a height-independent creatinine-based (full age spectrum, based on age (FASage)) and a cystatin C-based equation (FAScys), with the complex height-dependent CKiD3 equation incorporating gender, height, cystatin C, creatinine, and urea.
Mean had a P accuracy of 89.2% compared to mean 87.7% (p = 0.030) as well as lower bias and %precision error and performed almost as well as CKiD3 (P accuracy 90.9%). Modifying the weight of FASage and FAScys when calculating the means showed that an equal contribution was most accurate in most patients. In spina bifida patients, FAScys alone outperformed any combination. Malignancy or nephritis patients had slightly higher accuracy with weighted means favoring cystatin C or creatinine, respectively. Disagreement between FAScys and FASage was inversely correlated with the accuracy of mean. When disagreement exceeded 40%, application of weighted means based on diagnosis improved the performance of eGFR.
In the absence of height data, the optimal strategy for estimating GFR in children is by using the geometric mean of FASage and FAScys. When there is large disagreement between the two, weighted means based on diagnosis improve accuracy.
结合基于肌酐和胱抑素 C 的估算肾小球滤过率 (eGFR) 方程已被证明可提高 GFR 估计的准确性。本研究旨在优化该策略，以实现儿童身高独立的 GFR 估计。
回顾性研究了 408 例儿童使用菊粉清除率试验同时进行国际临床化学联合会校准的肌酐、胱抑素 C 和尿素测量（平均年龄 12.5 岁，GFR 91.2ml/min/1.73m），比较了身高独立的基于肌酐的（全年龄谱，基于年龄（FASage））和基于胱抑素 C 的方程（FAScys）的算术（均值）和几何均值（均值），与复杂的依赖身高的 CKiD3 方程（纳入性别、身高、胱抑素 C、肌酐和尿素）。
平均与平均相比，准确度为 89.2%，准确性提高 87.7%（p=0.030），且偏倚和%精度误差较低，与 CKiD3 表现相当（准确度 90.9%）。在计算均值时，修改 FASage 和 FAScys 的权重表明，在大多数患者中，平等贡献最为准确。在脊柱裂患者中，单独使用 FAScys 优于任何组合。恶性肿瘤或肾炎患者分别使用胱抑素 C 或肌酐加权均值时，准确性略有提高。FAScys 和 FASage 之间的差异与均值的准确性呈反比。当差异超过 40%时，基于诊断应用加权均值可提高 eGFR 的性能。
在没有身高数据的情况下，估计儿童 GFR 的最佳策略是使用 FASage 和 FAScys 的几何均值。当两者之间存在较大差异时，基于诊断的加权均值可提高准确性。
