Comparison of eGFR Values Calculated by Using Serum Cystatin C and Serum Creatinine in Patients with Diabetes Mellitus

Abstract

Objective: In this study, we aimed to compare estimated glomerular filtration rate (eGFR) formulas based on cystatin C and serum creatinine and investigate whether the formulas can detect the renal damage at microalbuminuric level in diabetic patients. Methods: Totally, 99 type 2 diabetic patients were included and divided into 3 groups according to 24 hour urine albumin levels as normoalbuminuric group (group 1), microalbuminuric group (group 2) and macroalbuminuric group (group 3). Creatinine clearance, Cockcroft-Gault (C-G), Modification of Diet in Renal Disease (MDRD), The Chronic Kidney Disease Epidemiology (CKD-EPI), eGFR1, eGFR2 and eGFR3 levels were calculated using formulas. Results: There were significant differences between group 1-3 and group 2-3, but there was no significant difference between group 1 and 2 in calculated GFR levels. Cystatin C-based formulas were found to have a better correlation with creatinine clearance. Conclusion: As a result, cystatin C-based formulas were found to predict creatinine clearance better than the other calculated GFR formulas in diabetic patients. However none of the formulas can discriminate the renal damage at microalbuminuric level. J Clin Exp Invest 2015; 6 (2): 91-95 Key words: eGFR, cystatin C, diabetic nephropathy, creatinine, CKD-EPI