The change of serum cystatin C and its clinical significance in type 2 diabetic patients with different stage of renal impairment

Objective To investigate the change of serum cystatin C(Cys-C) in different stage of renal impairment in type 2 diabetic patients and evaluate the diagnostic value of serum Cys-C at early renal impairment in type 2 diabetes.Methods The level of serum cystatin C was detected by particle-enhanced immunonephelometry in 137 patients with type 2 diabetes mellitus(including 78 cases of diabetic nephropathy).Urinary albumin excretion rate(UAER),serum albumin,creatinine,blood urea nitrogen(BUN) were detected at the same time,and then the glomerular filtration rate(GFR) were calculated by MDRD equation.Results There was significant difference in serum level of Cys-C between normal albuminuria group and microalbuminuria group(P0.05),and the latter was significantly different from macro-albuminuria group in serum level of Cys-C(P0.01).The serum cystatin C in both micro-albuminuria group and macro-albuminuria group was significantly correlative to the glomerular filtration rate(P0.01).Conclusion Serum cystatin C can be used as a marker in early renal impairment in type 2 diabetes mellitus.