Diagnostic value of measuring urinary cystatin C in early diabetic nephropathy

AIM: To investigate the levels of urinary Cystatin C, β 2-microglubin and albumin in different stages of diabetes mellitus and to explore the diagnostic value of urinary Cystatin C in early diabetic nephropathy. METHODS: The urinary albumin andβ 2-microglubin were detected by radioimmunoassay (RIA) and Cystatin C was detected by enzyme immunoassay. RESULTS: With UAER30 mg 24 h urine-1, the level of urinary Cystatin C(0.28±0.09) mg/L was significantly higher than that in the normal group (0.15± 0.08) mg/L (P0.01), and the β 2-microglubin (0.10±0.04) mg/L and the albumin (6.22±1.41) mg/L were significant higher than those in the normal group (0.04± 0.03) mg/L and (3.54±2.42) mg/L, (P0.05). With UAER in 30-300 mg 24 h urine-1, the levels of urinary Cystatin C, β 2-microglubin and albumin increased significantly (P 0.01). CONCLUSION: The levels of urinary Cystatin C, β 2-microglubin and albumin in diabetes mellitus patients are significant higher than those in the normal group, of which the level of Cystatin C increases significantly at early stage, so the Cystatin C is a sensitive index for the early injure of renal in diabetes mellitus.