碘海醇血浆清除率测定肾小球滤过率与临床常用的估算肾小球滤过率方法的比较

Comparison of GFR measured by iohexol plasma clearancewith common clinical methods for evaluating glomerularfiltration rate

目的采用碘海醇血浆清除率测定肾小球滤过率(mGFR)与临床常用方法评估估算肾小球滤过率(eGFR)的准确性比较。方法选取2019年6月至2020年6月在本院自愿参加测试的145例研究对象,根据eGFR值进行分组:1期[eGFR≥90 mL·(min·1.73 m2)-1,37例]、2期[eGFR 60~90 mL·(min·1.73 m2)-1,39例]、3期[eGFR 30~60 mL·(min·1.73 m2)-1,47例]、4期[eGFR 15~30 mL·(min·1.73 m2)-1,17例]、5期[eGFR<15 mL·(min·1.73 m2)-1,5例],所有研究对象通过静脉注射碘海醇5 mL后,在注射后0、2 h和4~6 h间取血浆样本3次,测量血浆清除率,进行肾功能评估,并与常用的肾功能评估公式[MDRD、内生肌酐清除率(Ccr)、CKD-EPI、Cockcroft-Gault]进行比较。结果Ccr、MDRD公式计算eGFR值高于采用碘海醇血浆清除率计算的mGFR值(均P<0.05),而Cockcroft-Gault、CKD-EPI公式与采用碘海醇血浆清除率计算的mGFR值相比,差异均无统计学意义(均P>0.05)。与采用碘海醇血浆清除率计算的mGFR值的相关性依次为CKD-EPI公式(r=0.923)、Cockcroft-Gault公式(r=0.832)、Ccr公式(r=0.798)、MDRD公式(r=0.738)。MDRD公式在1、2、3、4期中的eGFR值高于碘海醇血浆清除率计算的mGFR值(均P<0.05);Cockcroft-Gault公式在1、2期中的eGFR值高于碘海醇血浆清除率计算的mGFR值(均P<0.05);CKD-EPI公式在3期中的eGFR值高于碘海醇血浆清除率计算的mGFR值(P<0.05);Ccr公式在3、4期中的eGFR值高于采用碘海醇血浆清除率计算的mGFR值(均P<0.05)。在1~3期中,CKD-EPI公式与碘海醇血浆清除率计算mGFR值的相关性最高(P<0.001)。CKD-EPI公式有相对较好的准确度和精确度,偏差中位数及偏差四分位间距均较少,P20和P30符合率相对较高。结论CKD-EPI公式与碘海醇血浆清除率公式计算的mGFR具有相关性,准确性高,其次为Cockcroft-Gault公式,而Ccr、MDRD公式在本研究中的相关性及准确性较差,在mGFR≤30 mL·(min·1.73 m2)-1中,各公式可能均与碘海醇血浆清除率计算的mGFR的相关性较差。

Objective To compare the accuracy of GFR measured(mCFR)by iohexol plasma clearance with that of commonly used clinical methods in estimated glomerular filtration rate(eGFR).MethodsA total of 145 volunteers who were tested in our hospital from June 2019 to June 2020 were recruited.Group according to eGFR value:stage1[eGFR≥90mL·(min·1.73m²)-1,37cases],stage 2[eGFR 60-90 mL·(min·1.73m²)-1,39 cases],stage 3[eGFR 30-60mL.(min·1.73m²)-1,47cases],stage4[eCFR15-30mL(min·1.73m²)-,17cases],stage5[eGFR<15-30 mL·(min·1.73m²)-,5 cases].After intravenous injection of iohexol 5 mL,plasma samples were collected at 3 different time points.The blood collection points were at O,2 hours,and 4-6 hours.The plasma clearance rate of iohexol was tested,and mGFR.Then,mGFR value calculated by iohexol plasma clearance rate was compared with the commonly used renal function evaluation formulas.Results eGFR calculated by Ccr and MDRD formula was higher than mGFR calculated by iohexol plasma clearance rate(all P<0.05),while there was no significant difference between Cockcroft-Gault,CKD-EPI formula and the mGFR calculated by iohexol plasma clearance rate(all P>0.05).The correlation between mCFR value calculated by iohecol plasma clearance rate was CKD-EPI formula(r=0.923),Cockcroft-Gault formula(r=0.832),Ccr formula(r=0.798),MDRD formula(r=0.738).eGFR value calculated by MDRD formula was higher than the mGFR value calculated by the plasma clearance rate of iohexol in stage 1,2,3 and 4(all P<0.05).The eGFR value calculated by Cockcroft-Gault formula was higher than the mGFR value calculated by the plasma clearance rate of iohexol in stage 1 and 2(all P<0.05).The CKD-EPI formula was higher than the mGFR value calculated by the plasma clearance rate of iohexol in three stages(P<0.05).The eCFR value calculated by Ccr formula was higher than the mGFR value calculated by iohexol plasma clearance rate in stage 3 and 4(all P<0.05).The CKD-EPI formula had the highest correlation with the mGFR value calculated by iohexol plasma clearance rate in 1-3 stages(P<0.001).CKDEPI formula had relatively good accuracy and accuracy,the median deviation and interquartile deviation are less,and the coincidence rate of P20 and P30 was relatively high.ConclusionSsCKD-EPI has a good correlation and accuracy in the overall subjects,followed by the Cockcroft-Gault formula,while Cer and MDRD has a poor correlation in this study.All formulas have poor correlation with mGFR value calculated by iohexol plasma clearance rate[mGFR≤30 mL·(min·1.73 m)-1].