三种肾小球滤过率检测方法的实用性探讨

目的：以^99mTc—DPTA血浆清除率为标准，对24h内生肌酐清除率（Ccr）、Cookeroft—Gault（CG）方程和简化MDRD（modification of diet in renal disease）方程进行比较，评价三种方程在慢性肾脏疾病（CKD）患者中的应用。方法：选择139例各种慢性肾脏疾病患者，将Ccr、CG方程和简化MDRM方程估算的肾小球滤过率（GFR）用体表面积（BSA）标准化，与BSA标准化的^99mTc—DTPA测得的GFR（^99mTc—GFR）在不同CKD分期进行比较。结果：CKD第一至第五期：Ccr与^99mTc—GFR相关系数r分别为：0．79、0．71、0．64、0．59、0．52；Ccr在ROC曲线下面积平均为0．79。CG—GFR与^99mTc—GFR相关系数r分别为：0．85、0．78、0．72、0．67、0．61；CG—GFR在ROC曲线下面积平均为0．83。MDRD—GFR与^99mTc—GFR相关系数r分别为：0．83、0．76、0．69、0．65、0．59；MDRD—GFR在ROC曲线下面积平均为0．82。在CKD不同分期三种方程的GFR估算值与^99mTc—GFR差异均有显著意义（P均〈0．001）。结论：三种方程的GFR估算值与^99mTc—GFR均有较好的相关性和ROC曲线下面积，以CG方程最好，其次为简化MDRD方程，Ccr最低，但三种方程估算值与^99mTc—GFR测定值差异均有显著意义。上述方程直接应用于我国CKD患者时，应对其进行适当修正。     

7种肾小球滤过率评估方程在慢性肾脏病患者中的比较

目的：比较不同肾小球滤过率（GFR）评估方程在慢性肾脏病（CKD）患者中的诊断价值。方法：选择CKD各期患者108例,对照20例,应用ELISA法测定血清Cystatin C浓度、^99m Tc-DTPA清除率测定GFR、全自动生化分析仪检测血清肌酐（Scr）,并用7种公式计算GFR（eGFR）。结果：在CKD2期,MDRD、简化MDRD与GFR比较有统计学差异,在CKD3期,CG-eGFR与GFR比较有统计学差异。而Cys-eGFR在CKD1～5期与GFR均无统计学差异。在CKD2期、3期,4种Cys-eGFR方程与GFR的相关性均显著优于CG和MDRD公式。而在1期、4期和5期,各方法测定eGFR与同位素GFR的相关性相当。在GFR〈60ml.min^-1.1.73m^-2的CKD患者中,4种Cys-eGFR的ROC曲线下面积大于Cr-eGFR方程,有统计学意义;在GFR〈30ml.min^-1.1.73m^-2的CKD患者中,ROC曲线下面积比较无统计学差异。结论：cys-eGFR在肾功能轻中度减退的患者中,优于CG和MDRD,在肾衰竭后期,诊断价值同Cr-eGFR公式。     

三种肾小球滤过率评估方程在正常人群中的应用

目的评价99mTc-DTPA肾动态显像(Gates′分析法)、简化MDRD及CKD-EPI公式测量的肾小球滤过率(GFR)对正常人群肾功能的诊断效能。方法收集2011年9月至2018年10月在本院行术前肾动态显像的117例健康肾移植供体为研究对象, 分别用Gates′分析法(采用T?nnesen公式)、简化MDRD及CKD-EPI公式计算肾GFR, 以CT测量肾脏深度计算的GFR为参考方法, 比较各种方法计算的GFR诊断肾功能的准确性。结果简化MDRD公式计算的GFR高于CT测量(P<0.01);T?nnesen公式计算的GFR低于CT测量(P<0.01);CKD-EPI公式计算的GFR与CT测量比较, 差异无统计学意义(P>0.05)。结论 CKD-EPI公式可以代替CT测量计算GFR, 适合正常人群的肾功能筛查。     

Cystatin C相关方程在计算慢性肾脏病肾小球滤过率的对照研究

目的 评价血清半胱氨酸蛋白酶抑制剂C（Cystatin C，CysC）相关方程在不同病因引起慢性肾脏病（CKD）患者的肾小球滤过率（GFR）计算中的临床应用价值。方法选择CKD患者255例，运用MDRD方程（mGFR）、MDRD简化方程（rnGFR）、Hoek方程（hGFR）、2006年中华医学会肾脏病学分会推荐的方程（c-cGFR1，c-cGFR2）计算GFR，与^99m-二乙撑三胺五乙酸（^99m TcDT-PA）肾动态显像测得的。肾小球滤过率（sGFR）进行比较。结果在分期比较中，各方程估算的GFR和sGFR相关性一般，CysC相关方程能更敏感反应GFR；在不同病因分组中，各方程估算的GFR和sGFR均明显相关，特别是c-cGFR2。结论在CysC相关方程中，以2006中华公式2计算的c-cG-FR2与sGFR相关性及一致性最好，并且在糖尿病肾脏病组中，各方程相关系数优于其他组别，有必要进一步大规模临床研究证明其应用价值。     

CKD—EPI方程在慢性肾脏病患者中的适用性

目的探讨慢性。肾脏病流行病学合作研究（CKD-EPI）方程对评估中国人肾小球滤过率（GFR）的适用性。方法选择CKD患者42例,对其以CKD-EPI方程估算GFR（eGFR）与BSA标准化的99mTc-DTPA肾动态显像法测定的GFR（sGFR）进行比较。结果eGFR与sGFR呈正相关（r=0．868,P〈0．01）;eGFR的15％、30％及50％符合率分别是23．8％、40．5％和64．3％,eGFR与sGFR平均偏差5．46ml／min。结论CKD-EPI方程可广泛应用于评估CKD患者GFR,但仍然存在偏差,需进行大规模试验并根据CKD不同分期进行适用性研究。     

CKD-EPI方程对基于简化MDRD方程的慢性肾脏病患者分期的影响

目的 研究CKD-EPI方程对基于简化MDRD方程的慢性肾脏病（CKD）患者分期的影响。 方法 选择2008年6月至2009年9月在我院肾内科就诊的CKD患者450例,分别用简化MDRD方程和CKD-EPI方程估测GFR（eGFR）。用Bland-Altman曲线对二方程计算的eGFR进行一致性检验。根据eGFR对CKD患者分期,对基于不同方程的CKD患者的分期情况进行Kappa检验。 结果 简化MDRD方程和CKD-EPI方程估测eGFR的一致性好,但CKD-EPI-eGFR较MDRD-eGFR平均高出约2.4 ml·（min）-1·（1.73 m2）-1。简化MDRD方程和CKD-EPI方程在CKD1、2、3A、3B、4 和5期符合率分别为97.10%（n=67）,80.77%（n=105）,60.86%（n=48）,87.69%（n=57）,90.38%（n=47）和98.18%（n=54）。Kappa检验提示2方程对CKD患者分期的一致性极好[Kappa值0.913（95%CI：0.881~0.945）]。然而,若依据CKD-EPI方程结果,仍须将由简化MDRD方程分类至60～89 ml·（min）-1·（1.73 m2）-1及45～59 ml·（min）-1·（1.73 m2）-1两组中的19.23%（n=25）及39.24%（n=31）的患者进行再次分类,且均被归为更高eGFR等级。 结论 CKD-EPI方程可“上调”基于简化MDRD方程的CKD 2期～3A期患者的分期等级,纠正了简化MDRD方程对CKD的过度诊断。     

不同方法对肾功能评估的价值

目的探讨临床上常用的几种肾功能评估方法的相对准确性,寻求更为简便、快捷的肾功能评估方法。方法选择慢性肾脏病（CKD）患者80例,分别用^99mTc-DTPA肾动态显像法测定肾小球滤过率（GFR）,同时检测患者血肌酐（SCr）、血清胱抑素C（CysC）浓度,根据SCr分别用Cock-croft-Gault（C-G）方程和简化MDRD方程估算肾小球滤过率（分别为eGFR1、eGFR2）。按GFR值将患者分为4组,即A组：CKD1期;B组：CKD2期;C组：CKD3期;D组：CKD4期;排除CKD5期的患者。观察所有和各组患者eGFR1、eGFR2、SCr、CysC与GFR的相关性。结果总样本中,eGFR1、eGFR2与GFR呈正相关,SCr、CysC与GFR呈负相关（P〈0．01）。在各组中,A组：eGFR1、eGFR2、SCr与GFR之间均无明显相关性（P〉0．05）;而B、C、D组中eGFR1、eGFR2与GFR呈正相关（P〈0．01）,SCr与GFR呈负相关（P〈0．05）;CysC在A、B、C、D各组中均与GFR呈负相关（P〈0．01）。结论CKD2、3、4期患者eGFR1、eGFR2、SCr与GFR均有一定的相关性,但不论何期CKD患者,CysC均能准确反映其肾功能状况,且更加简便、快捷。     

CKD—EPI方程在我国慢性肾脏病不同分期中的应用

目的探讨慢性肾脏病流行病学合作研究（CKD-EPI）方程在中国人CKD的不同分期评估肾小球滤过率（GFR）的适用性。方法选择我院肾内科CKD患者98例。将CKl2vEPI方程估算的GFR值用体表面积（BSA）标准化得出估算GFR（eGFR）,与BsA标准化的肾动态显像法（^99Tc-DTPA）检测的GFR（sGFR）用K／DOOI指南推荐的方法进行比较。结果相关性分析得出eGFR与sGFR呈正相关（r=0．847,P〈0．01）;eGFR的15％、30％及50％符合率分别是31．6N、59．2％和85．7％,eGFR估计值与sGFR平均偏差2．56ml／min。CKD各期偏差均无统计学意义,在CKD2～5期,偏差较小;CKD1期,偏差略大,偏差值为（13．22±22．41）,但偏差无统计学意义（P〉0．05）。结论CKD-EPI方程可广泛应用于我国CKD各期患者评估GFR,具有较小的偏差,较高的准确性。CKD-EPI方程在评估较高的GFR时,可能存在矫枉过正,高估GFR。     

三种肾小球滤过率预测公式在肾脏肿瘤患者肾功能评估中的应用

目的:评价肾小球滤过率(GFR)预测公式在肾肿瘤患者肾功能评估中的应用价值。方法:选取2010年9月~2013年6月收治的肾肿瘤患者73例,以99mTc-DTPA肾动态显像法测得的rGFR为金标准,计算慢性肾脏病流行病学合作研究(CKD-EPI)公式、简化MDRD公式及中国改良简化MDRD公式的预测eGFR与其相关性,及不同分割点时各公式诊断的敏感性。结果:三个公式的eGFR值与rGFR值有很好的相关性(相关系数分别为r=0.658,P=0.001;r=0.806,P=0.000;r=0.795,P=0.000)。当分别以90或60ml·min-1·1.73 m-2为诊断分割点时,受试者工作特征曲线(ROC)曲线下面积比较差异无统计学意义。结论:3种公式均具有较好的预测肾脏肿瘤患者GFR的能力,可作为有效的肾功能评价的指标。     

六种肾小球滤过率估算方程对梗阻性肾病患者肾小球滤过率的比较

目的:比较六种肾小球滤过率估算方程在评价中国梗阻性肾病患者肾小球滤过率(Glomerular filtration rate,GFR)的适用性,即3种MDRD(Modification of Diet in Renal Disease,MDRD)公式和3种CKD-EPI(Chronic Kidney Disease Epidemiology Collaboration,CKD-EPI)公式。方法:选择2012年01月~2016年12月在我院完成99 m Tc-DTPA肾动态显像(ECT)检查的梗阻性肾病患者476例,以ECT所测得的GFR(m GFR)作为参考标准,用目前常用以上6种方程估算GFR(e GFR)为对照,分析各e GFR与m GFR的相关性,并就6种e GFR的估测偏差、精确度、准确率及诊断准确性进行比较。结果:本研究结果表明各e GFR与m GFR均显示高度的相关性(P0.01)。在数值诊断上,各e GFR与CKD-EPI联合方程e GFR间的估测偏差、精确度、15%、30%及50%范围的准确度比较差异有统计学意义(P0.05)。CKD-EPI方程较MDRD方程显示出较好的数值准确度,CKD-EPI联合方程所估算的GFR在数值上准确度最高。在诊断方面,3种CKD-EPI方程的ROC曲线下面积、分期诊断准确度及其一致性比3种MDRD方程更好,其中,CKD-EPI联合方程ROC曲线下面积最大(0.886),分期诊断准确度最高(44.1%),Kappa值最大(0.254,CI[0.179,0.311])。在亚组分析中,不同的亚组最适方程有所差别,其中简化MDRD与CKD-EPI联合方程在不同亚组中的适用性较高。结论:CKD-EPI方程对中国的梗阻性肾病患者较MDRD方程有更高的适用性,其中CKD-EPI联合方程所估算的e GFR值与m GFR值相关性最好,准确度最高,偏倚最小,诊断性能最好。     

Evaluation of methods based on creatinine and cystatin C to estimate glomerular filtration rate in chronic kidney disease

Purpose

Estimated glomerular filtration rate (GFR) is a useful tool for the detection of chronic kidney disease (CKD). Several methods have been proposed, but findings can vary in specific groups such as patients with diabetes, elderly and high and low body mass index and, also, with the stage of CKD. The objective of this study was comparing the accuracy of the currently used equations for estimating GFR with that of the gold standard technetium-(99m)-diethylene triamine pentaacetic acid (99mTc-DTPA).

Methods

We performed a cross-sectional study of 129 patients with all five CKD stages. GFR was estimated using the following: 24-h urine creatinine clearance, Cockcroft–Gault equation, MDRD equation, CKD-EPI equation, Hoek’s cystatin C equation, and isotopic 99mTc-DTPA (as gold standard). We evaluated agreement in the whole study population and according to age, sex, weight, and diabetes.

Results

All methods had good agreement. The best agreement was observed with the cystatin C [intraclass coefficient correlation (ICC) 95 % confidence interval (95 % CI), 0.87 (0.82–0.91)], followed by CKD-EPI [ICC 0.83 (0.77–0.88)]. Twenty-four-hour urine creatinine clearance showed the worst agreement in patients older than 65 years [ICC 0.70 (0.56–0.79)]. The Cockcroft–Gault equation showed the worst agreement in younger than 65 years [ICC 0.64 (0.42–0.79)]. The best agreement for classification in the correct CKD stage was with the cystatin C equation [κ = 0.80 (0.74–0.87)]. GFR was overestimated with all methods in CKD stages 4 and 5.

Conclusions

The methods used in clinical practice are adequate for classification of CKD. Cystatin C is the most accurate method, followed by CKD-EPI. The Cockcroft–Gault equation is not accurate in young patients. Twenty-four-hour urine creatinine clearance loses accuracy in patients aged older than 65 years.     

Which Method of GFR Estimation Has the Best Prognostic Value in Patients Treated with Primary PCI: Cockcroft–Gault Formula,MDRD, or CKD-EPI Equation?—A 6-Year Follow-Up

Background/aims: The aim of this study was to determine the correlation between renal function and 6-year mortality in patients with acute myocardial infarction (AMI), treated successfully with primary percutaneous coronary intervention (PCI), and to examine whether Cockcroft–Gault (C-G) formula or Modification of Diet in Renal Disease (MDRD) study equation or CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation is the best predictor of very late mortality. Methods: A prospective cohort study with 6-year follow-up of a homogenous group of 193 patients, with ST-segment elevation AMI treated with successful primary PCI. Glomerular filtration rate (GFR) estimated by C-G formula, MDRD, and CKD-EPI equation were analyzed. Results: The patients with chronic kidney disease (CKD) had a much lower cumulative survival rate than those without it (p < 0.05). A larger area under the receiver-operating characteristic curve for death with respect to GFR for C-G formula was observed. In the multivariate analysis, only GFR ≥ 55 mL/min according to C-G formula was independently associated with lower mortality. Conclusion: CKD is associated with higher mortality after a successful primary PCI during a 6-year follow-up. C-G formula is better than MDRD and CKD-EPI equations at predicting mortality after AMI.     

中国肾小球滤过率评估方程在慢性肾小球肾炎患者的适用性评价

目的：评价现有在中国人群基础上开发的肾小球滤过率（GFR）评估方程在慢性肾小球肾炎患者的适用性。方法：选择143例慢性肾小球肾炎患者,用中国方程、瑞金方程、MDRD1方程和简化MDRD方程,分别计算GFR值,与^99mTc—DTPA测的GFR（sGFR）进行比较。结果：Bland—Altman分析显示MDRD1方程和瑞金方程估计的GFR和sGFR的一致性较好,但所有各方程估计的GFR和出FR的一致性限度均超过事先规定的专业界值。线性回归结果显示,MDRD1方程和瑞金方程估测的GFR与X轴的斜率较其他方程更接近0。在所有方程中,MDRD1方程和中国9方程偏差较小,瑞金方程估测GFR30％符合率和50％符合率均最高,但瑞金方程估测GFR30％符合率依然低于70％。在慢性肾脏病不同分期中,瑞金方程和MDRD1方程较其他方程有较小的偏差和更优的准确性。结论：当血肌酐的测定方法为酶法时,如直接应用现有在中国人群基础上开发的肾小球滤过率评估方程评估慢性肾小球肾炎患者肾功能,可能会产生明显的偏差。     

Evaluation and applicability of predictive equations of the glomerular filtration rate in chronic kidney disease

Prediction equations of glomerular filtration rate (GFR) may facilitate early detection, evaluation and management of chronic kidney disease (CKD). However, the reliability of these equations was not extensively studied in our CKD population. Hence, the present study was aimed to determine the performance of modification of diet in renal disease (MDRD) and Cock-croft Gault formulas in predicting GFR in CKD patients and their relationship with the measured GFR. A total of 104 subjects (71 male and 33 female, aged 26-68 years) with different stages of CKD were recruited for this study; we excluded 51 patients due to improper collection of 24-h urine. The GFR was measured using 24-h creatinine clearance and predicted by the Cockcroft Gault, the 4-variable MDRD and the 6-variable MDRD equations. Prediction equations correlated well with the measured GFR. However, the predicted GFR using the 4-variable MDRD equation revealed a highly significant positive correlation with the GFR measured by creatinine clearance (r = 0.86, P < 0.001), followed by the 6-variable MDRD and Cockcroft-Gault equations with r = 0.85 and 0.77, P < 0.001, respectively. In conclusion, the present study predicts that the 4-variable MDRD is the best available equation for predicting GFR in our CKD population.     

Modified glomerular filtration rate estimating equation for Chinese patients with chronic kidney disease

The Modification of Diet in Renal Disease (MDRD) equations provide a rapid method of assessing GFR in patients with chronic kidney disease (CKD). However, previous research indicated that modification of these equations is necessary for application in Chinese patients with CKD. The objective of this study was to modify MDRD equations on the basis of the data from the Chinese CKD population and compare the diagnostic performance of the modified MDRD equations with that of the original MDRD equations across CKD stages in a multicenter, cross-sectional study of GFR estimation from plasma creatinine, demographic data, and clinical characteristics. A total of 684 adult patients with CKD, from nine geographic regions of China were selected. A random sample of 454 of these patients were included in the training sample set, and the remaining 230 patients were included in the testing sample set. With the use of the dual plasma sampling (99m)Tc-DTPA plasma clearance method as a reference for GFR measurement, the original MDRD equations were modified by two methods: First, by adding a racial factor for Chinese in the original MDRD equations, and, second, by applying multiple linear regression to the training sample and modifying the coefficient that is associated with each variable in the original MDRD equations and then validating in the testing sample and comparing it with the original MDRD equations. All modified MDRD equations showed significant performance improvement in bias, precision, and accuracy compared with the original MDRD equations, and the percentage of estimated GFR that did not deviate >30% from the reference GFR was >75%. The modified MDRD equations that were based on the Chinese patients with CKD offered significant advantages in different CKD stages and could be applied in clinical practice, at least in Chinese patients with CKD.     

^99mTc—DTPA测定肾小球滤过率在移植肾活体供体中的应用价值

目的制定^99mTc—DTPA测定肾小球滤过率（GFR）在不同年龄组中的正常参考范围,评价其在移植。肾活体供体中的临床价值。方法300例移植肾供体行肾动态显像,应用Gates法计算GFR,统计分析GFR正常参考范围及不同年龄组GFR正常参考范围,分析其与性别、年龄、身高体重指数的关系。结果300例供肾者左肾、右肾及总肾的GFR为（49．25±10．34）mL／min、（49．27±9．69）mL／min及（98．52±19．03）mL／min;〈50岁者的GFR显著高于≥50岁者,〈50岁或≥50岁,各年龄组间GFR无显著性差异;Logistic回归分析表明GFR仅与年龄相关。始论：^99mTc-DTPA肾动态显像测定GFR方法简便、可靠,可以反映分肾功能、评估尿路排泄情况,对筛选移植肾供体具有一定价值。