Clinical application and evaluation of eight estimation equations for glomerular filtration rate in patients with post-operative renal carcinoma

ObjectiveTo evaluate the diagnostic performances of eight estimation equations for estimated glomerular filtration rate(eGFR)in patients with post-operative renal carcinoma.

MethodsA total of 237 patients with post-operative renal carcinoma were included as study objects.The glomerular filtration rate(GFR) measured by ^99mTc-DTPA renal dynamic imaging as reference(rGFR) were compared with the eight eGFR estimation equations respectively.Patients were divided into different groups according to body mass index, age, rGFR ect., and the clinical applicability of various equations in each group was compared.

ResultsCompared with rGFR, the GFR values were overestimated by all the other equations except Xiangya equation.The eGFR from the Xiangya equation demonstrated the highest precision and accuracy in whole population and almost all subgroups, followed by modified CKD-EPI equation(EPI-cn), while the G-C equation showed the poorest predictive value in precision and accuracy.The eGFR from EPI equation had the highest consistency with rGFR in rGFR >90 mL·min^-1·1.73m^-2 group; Xiangya equation demonstrated the best predictive value in rGFR 60-90 mL·min^-1·1.73m^-2 group; in the rGFR < 60 mL·min^-1·1.73m^-2 group, all equations were significantly overestimated.The P30 value of Xiangya equation, which had the highest precision and accuracy in all estimation equations, was only 69.54%, and the overall consistency with rGFR was still poor.

ConclusionsThere are some differences between eGFR from the equations and rGFR, especially when renal function declines.Renal dynamic imaging should be used in the preoperative renal function evaluation.The EPI and Xiangya equations should be applied together in the estimation of eGFR in postoperative renal function, and the impact of eGFR decline rate on the predictive value needs extra attention.