Mahajan Sandeep, Mukhiya Gulshan K, Singh Rajvir, Tiwari Suresh C, Kalra Vikram, Guleria Sandeep, Agarwal Sanjay K, Bhowmik Dipankar M, Gupta Sanjay, Dash Suresh C
Department of Nephrology, All India Institute of Medical Sciences Ansari Nagar, New Delhi, India.
Nephron Clin Pract. 2005;101(3):c128-33. doi: 10.1159/000086683. Epub 2005 Jul 5.
Accurate measurement of donor renal function has important long-term implications for both the donor and recipient. As the use of recommended filtration markers is limited by cumbersome and costly techniques, renal function is typically estimated using 24-hour urinary creatinine clearance (urine-CrCl). Prediction equations used for rapid bedside estimation of glomerular filtration rate (GFR) are simple and overcome the inaccuracies of urinary collection and, if validated, can expedite the donor workup besides reducing the cost. We assessed the suitability of urine-CrCl and prediction equations for evaluating potential Indian renal donors.
173 consecutive renal donors were enrolled. The predictive capabilities of the Cockcroft and Gault equation for creatinine clearance (CrCl) corrected for body surface area (CG-CrCl), CG-CrCl corrected for GFR (CG-GFR), MDRD-1, MDRD-2 and urine-CrCl were evaluated with 99mTc-diethylenetriaminepentaacetic acid (DTPA)-GFR as reference GFR.
The study population had a mean age of 44.1 years with 74% being females. Mean DTPA-GFR was 83.85 ml/min/1.73 m2. The median percent absolute difference was most with urine-CrCl and least with CG-GFR (21.84 and 13.82). The Pearson's correlation varied from 0.08 to 0.26 (urine-CrCl and MDRD-1). The precision was most with MDRD-1 and least with urine-CrCl (0.07 and 0.01). The bias was least with CG-GFR and most with MDRD-2 (1.34 and 17.16). The number of subjects with predicted GFR values within 30% of DTPA was most with MDRD-1 (86%) and least with urine-CrCl (69%). The sensitivity for selecting a donor with a GFR of > or = 80/ml/min/1.73 m2 was the most with CG-GFR (65.7%), while specificity was maximum with MDRD-2 (90.1%).
Our results in potential Indian renal donors show that of all the prediction equations MDRD-1 is the most precise and accurate, while CG-GFR is the least biased. However, the poor correlation and level of error exhibited by these equations makes them suboptimal for donor evaluation.
准确测量供体肾功能对供体和受体都具有重要的长期意义。由于推荐的滤过标志物的使用受到技术繁琐和成本高昂的限制，肾功能通常使用24小时尿肌酐清除率（尿CrCl）来估算。用于快速床边估算肾小球滤过率（GFR）的预测方程简单，克服了尿液收集的不准确性，并且如果经过验证，除了降低成本外，还可以加快供体检查流程。我们评估了尿CrCl和预测方程在评估潜在印度肾供体方面的适用性。
连续纳入173名肾供体。以99mTc-二乙三胺五乙酸（DTPA）-GFR作为参考GFR，评估了Cockcroft和Gault方程对体表面积校正后的肌酐清除率（CG-CrCl）、对GFR校正后的CG-CrCl（CG-GFR）、MDRD-1、MDRD-2和尿CrCl的预测能力。
研究人群的平均年龄为44.1岁，74%为女性。平均DTPA-GFR为83.85 ml/min/1.73 m2。绝对差异百分比中位数在尿CrCl时最高，在CG-GFR时最低（分别为21.84和13.82）。Pearson相关性在0.08至0.26之间（尿CrCl和MDRD-1）。精密度在MDRD-1时最高，在尿CrCl时最低（分别为0.07和0.01）。偏差在CG-GFR时最小，在MDRD-2时最大（分别为1.34和17.16）。预测GFR值在DTPA的30%以内的受试者数量在MDRD-1时最多（86%），在尿CrCl时最少（69%）。选择GFR≥80/ml/min/1.73 m2的供体的敏感性在CG-GFR时最高（65.7%），而特异性在MDRD-2时最高（90.1%）。
我们在潜在印度肾供体中的研究结果表明，在所有预测方程中，MDRD-1最精确和准确，而CG-GFR偏差最小。然而，这些方程表现出的较差相关性和误差水平使其在供体评估中并非最佳选择。
