Assessing the Diagnostic Power of Cystatin C and Creatinine in Detection of Chronic Kidney Disease

In patients with renal disorders, a sudden decrease in glomerular filtration rate (GFR) would not result in rapid rise concentrations of Creatinine. The present study aimed to assess diagnostic accuracy of serum Cystatin C as an appropriate alternative to serum Creatinine for early detection of Chronic Kidney Disease (CKD).

In this study, 72 patients, 48 female and 24 male were selected. Serum Cystatin C and serum Creatinine were assayed, using enzyme-linked immunosorbent assay (ELISA) and routine methods, respectively. Glomerular filtration rate (eGFR) was estimated by Cockcroft and Gault formula. Receiver operating characteristics (ROC) analysis was adopted to evaluate diagnostic accuracy of serum Cystatin C and serum Creatinine.

Using Pearson's Correlation Coefficient analysis among Creatinine, Cystatin C and eGFR showed Serum Cystatin C was better than Creatinine. The sensitivity, specificity and AUC for Serum Cystatin C were 0.88, 0.70 and 0.85, and for Serum Creatinine, they  were 0.60, 0.80 and 0.68 respectively.

Our results showed that in early stages of CKD, Cystatin C is a more accurate biomarker for kidney function than Creatinine