A study on levels of serum cystatin C in different stages of renal impairment in patients with chronic kidney disease

Objective To detect the levels of serum cystatin C in the patients with chronic kidney disease(CKD),and to explore the changes of serum cystatin C in the different stages of CKD.Methods Accor ding to the clinical stage,the patients were divided into five groups:Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ stage of CKD group.The serum cystatin C levels of 68 normal controls and 106 CKD were tested.On the same time,serum creatinine and endogenous creatinine clearance were measured in all patients.Results There was significant difference on the level of serum cystatin C and endogenous creatinine clearance compared with Ⅰ stage of renal function in different renal diseases groups(P0.01).There was significant difference on the leves of serum cystatin C compared with nomal controls(P0.01).The level of serum cystatin C was positively correlated with SCr(r=0.781,P0.01),but it was negatively correlated with Ccr(r=-0.815,P0.01).The changes of serum cystatin C was more sensitive to SCr on early renal impairment.Conclusion Serum cystatin C is superior to serum creatinine as a marker of renal function and may show renal impairrment in the different stages of CKD.