肾小球滤过率计算公式的发展和比较

The development and comparison of estimated glomerular filtration rate equations

肾脏疾病的早期诊断依赖于对肾小球滤过率(GFR)的准确判断。为了简化GFR的临床应用,学者们开发了多个基于肌酐(Cr)及半胱氨酸蛋白酶抑制剂C(CysC)等滤过标志物的估算肾小球滤过率(eGFR)公式。最早开发的Cockcroft-Gault(C-G)公式基于慢性肾脏病(CKD)患者建立且例数较少,受到诸多因素的影响,目前认为其作为内生肌酐清除率的计算公式更为合适。而后建立的肾脏病膳食改良(MDRD)公式同样基于CKD患者,例数较多,但在健康人及非肾病患者中的准确性不佳,部分原因在于滤过标志物的测定并未标准化。但在Cr和CysC测定均标准化后其修正公式的应用仍不尽如人意。受到建立人群的限制,MDRD公式更适用于CKD患者。慢性肾脏病流行病学合作研究(CKD-EPI)公式建立人群不仅有CKD患者,还有更多健康人等,故其临床应用更佳。基于Cr的CKD-EPI公式准确性更优于Cr与CysC联合公式。eGFR公式简化了肾功能的了解和评价过程,但eGFR公式是由数学模型拟合而来。直接测定GFR(mGFR)方法的选择直接决定了建立的eGFR公式是否准确。滤过标志物的检测受到多种因素的影响,故持续推进滤过标志物检测的标准化也是对结果准确性的必要保障。受到人种、饮食、肌肉量等因素的影响,eGFR公式的准确性还有赖于在与建立人群相似的人群中应用。

The key to diagnose kidney diseases early relies on accurate judgement on glomerular filtration rate（ GFR）. Some estimated glomerular filtration rate（ eGFR） equations have been developed in order to facilitate clinical use of GFR based on such filtration markers as creatinine（ Cr） and cystatin C（ CysC）. The earliest equation is Cockcroft-Gault（ C-G） equation which relies on chronic kidney disease（ CKD） patients with a small quantity,and it could be influenced with so many factors. Nowadays,C-G equation is thought to be more fit for estimating endogenous creatinine clearance rate. Modification of diet in renal disease（ MDRD） equation developed later also relies on CKD patients with more subjects involved. However,it is not accurate being used in healthy subjects and non-kidney disease patients,which partially was led by the standardization problem of filtration marker determination. After Cr and CysC assay standardizations are completed,the MDRD equation performance in clinical use is still not quite ideal,because the equation is established upon CKD patients that it performs well in this limited subjects. The chronic kidney disease epidemiology collaboration（ CKD-EPI） equation is developed on CKD patients and more healthy subjects as well,thus its clinical use is much better. CKD-EPI equation based on Cr is more accurate than those based on Cr and CysC. The eGFR equations have simplifed the evaluating process of kidney function,however,they are fitted through mathematic models,so the chosen method of measured GFR（ mGFR） directly decides whether the developed eGFR equation would be accurate or not. Filtration marker determination could be influenced by so many factors,therefore the consistence of advancing the standardization of filtration markers is also a guarantee to the accuracy of the equations. Considering of the factors such as race,diet and muscle mass,the accuracy of eGFR equations depends on using in similar patients as the equation developing subjects.