Application of Cystatin C-based formulas for prediction of glomerular filtration rate / 中华检验医学杂志

ABSTRACT

Objective To investigate the applicability of Cys C-based formulas for prediction of GFR in Chinese patients with CKD.Methods A total of 176 adult patients with CKD including 90 males and 86 females collected from 4 hospitals located in different geographic regions of China (Beijing,Shanghai,Dalian and Changsha) were enrolled in this study from September 2007 to July 2009.The rGFR was measured using 99mTc-DTPA clearance rate two-sample method.Cystantic C was measured by PETIA and PENIA respectively.The results of eGFR in the Larsson formula,Grubb formula,Hoek formula,Filler formula,Stevens formula and Hojs formula were compared with the rGFR to evaluate the calculation coherence,bias,precision,accuracy and the performance of correct phasing of the formulas.Results The mean 99mTc-DTPA clearance was [40.70 ( 19.09 - 86.49)] ml · min-1 · ( 1.73m2 ) -1.Significant difference was witnessed in the evaluation of GFR estimation formulas calculated by PETIA and PENIA (P ＜0.01).ICC and Spearman correlation analysis revealed a significant correlation between eGFR and rGFR.The ICCs of eGFR and rGFR ranged from 0.874 to 0.938.Compared with rGFR,the 30％ accuracy of all the eight evaluation formulas using PETIA and PENIA method were lower than 60％.The percentages of correct phasing in all the 5 stages of CKD were not ideal.With these formulas,percentages of correct phasing from CKD stage 2 to CKD stage 4 were lower than 65％.The eGFRs were underestimated by formulas evaluated by PENIA in CKD stage 1.All the eGFRs were overestimated remarkably by all equations in CKD stage 5.Conclusions None of the eight Cys C based formulas are ideal for estimation of GFR in Chinese CKD patients,and they can not be applied to Chinese patients directly.For this patient population,further studies will be needed to develop a more accurate Cys C-based GFR estimation formula that includes ethnicity,age and other factors.