Comparison of 99mTc-DTPA and serum creatinine, cystatin C in detection of glomerular filtration rate: a retrospective clinical data analysis of 744 Chinese subjects.

Background: To compare the accuracy of various equations for estimating glomerular filtration rate.

Methods: Chronic kidney disease was classified by Tc-DTPA scintigraphy (reference glomerular filtration rate), estimating glomerular filtration rate was estimated using various formulas. The similarity to reference glomerular filtration rate decide the accuracy of estimating glomerular filtration rate.

Results: Overall, the Fengscr-cys equation had significantly higher accuracy and correct proportion in chronic kidney disease stage classification than other equations. The subgroup analysis showed that Fengscr-cys equation was slightly more precise than other equations both in the male and female patients. Moreover, in patients older than 60 years or whose reference glomerular filtration rate was above 60 ml/min, Fengscr-cys equation also showed better accuracy.

Conclusion: Our data suggest that estimating glomerular filtration rate equations evaluated by serum cystatin C were better than serum creatinine-based equations, estimating glomerular filtration rate equations evaluated by both serum creatinine and cystatin C were better than those evaluated by serum creatinine or cystatin C alone. Among all enrolled equations, Fengscr-cys equation might be the best one to evaluate glomerular filtration rate in general Chinese paticipants.