Estimation of cystatin C and inflammation marker levels in type 2 diabetes mellitus patients with microalbuminuria

Abstract

Serum cystatin C (CstC) is a type of protein produced by cells at the normal level; when the kidney is in normal condition or function, it inhibits the interstitial cysteine protease. The objective of the current study is to evaluate the levels of CstC and inflammation markers in type 2 diabetes mellitus (T2DM) patients with early diagnosed microalbuminuria (MBA) and find if there is a relationship between CstC and different parameters. Fifty T2DM patients with a mean age of 44.41 ± 6.51 years in the Al-Yarmouk Teaching Hospital were recruited according to the presence of MBA, and they were compared with 40 nondiabetic individuals with a mean age of 42.22 ± 5.33 years as control. Serum CstC, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) were estimated by enzyme-linked immunosorbent assay. The mean values of serum CstC, IL-6, and TNF-α in the diabetic patients with MBA were all significantly increased compared to those of the nondiabetic individuals (P < 0.001). In T2DM patients with MBA, there were positive correlations between serum CstC levels and serum creatinine, creatinine urea, and cystatin-c/creatinine ratio. Similarly, there was a strong positive correlation between serum CstC and serum of the inflammatory markers IL-6 and TNF-α. However, there was a negative association between CstC and the estimated glomerular filtration rate-Larson equation. The results of the current study suggest that serum CstC, IL-6, and TNF-α may potentially serve as biomarkers for the early detection of MAB in patients with T2DM.