Abstract
Background: Prevalence of chronic kidney disease (CKD) is increased worldwide. According to Kidney Disease Improving Global Outcomes guidelines, CKD is defined as abnormalities of kidney structure or function, present for >3 months with implications for health. In individuals with Type-2 diabetes, assessment of kidney function is mandatory, as diabetic nephropathy constitutes the major cause of CKD which leads to end-stage renal disease in diabetic patients. Cystatin-“C”, an alternative biomarker of kidney function, is a better predictor of CKD and is less affected by age, race, or muscle mass. Hence, the presence of elevated serum cystatin C is directly linked with risk of developing a progressive form of CKD.

Aim and Objectives: This study aims to evaluate the importance of serum cystatin C as a marker for early detection of CKD in diabetic and non-diabetic patients.

Materials and Methods: A total of 25 non-diabetics with CKD (Group-I) and 25 diabetics with CKD (Group-II) were included in the study. Cystatin C and glucose were estimated in the serum sample. Latex-enhanced immunoturbidimetric assay method was used for the estimation of serum cystatin-C. Random blood glucose was estimated using glucose oxidase-peroxidase method. Student’s t-test was used for comparison between CKD with non-diabetics and CKD with diabetics by SPSS statistical package version 20.0. “P” < 0.05 was considered as statistically significant. The results of the two groups are expressed as Mean ± SD.

Results: Serum cystatin-C levels were significantly increased (P < 0.001) in Group-I when compared to Group-II. There was a significant negative correlation (r = –0.447, P < 0.001) between serum cystatin C and estimating glomerular filtration rate was observed, which indicates that there is a possibility of renal damage in non-diabetic subjects.

Conclusion: Cystatin C can be used as a good alternative marker compared to creatinine for assessing severe kidney damage.