Combined examination of serum cystatin C, C reactive protein, and β-2 urine microglobulin for diagnosing type 2 diabetic nephropathy

Objective To investigate the clinical value of the combined examination of serum Cystatin C (Cys C),C reactive protein (CRP),and β-2 urine microglobulin (β 2-MG) in the diagnosis of type 2 diabetic nephropathy (DN).Methods 141 patients with diabetes mellitus (DM) from our hospital were divided into 3 groups according to urinary albumin excretion rate (UAER):42 cases in group B (UAER ＜ 20 μg/min),33 cases in group C (20 μ g/min ≤ UAER ≤ 200 μ g/min),and 36 cases in group D (UAER ＞ 200 tμ g/min).40 health persons without DM were seslected a control group (group A).The serum Cys C,CRP,and urine β 2-MG concentrations were measured in each group.The relationship between UAER and each indicator was evaluated by pearson' s correlation analysis,and the efficiencies of each indicator and combination examination were evaluated by ceiver operating characteristic (ROC) curve analysis.Results The Cys C,CRP,and β 2-MG concentrations were statistically higher in the DN patients than in the control group (P ＜ 0.05) and were higher in group C and D than in group B (P ＜ 0.05).In DM patients,Cys C,CRP,and β 2-MG positively correlated with UAER (r =0.65,0.46,0.53,respectively,P ＜ 0.05).ROC areas of combined examination were larger than that of each indicator.Conclusions Cys C,CRP,and β 2-MG are sensitive indicators for early diagnosing DN.Combined examination can improve the accuracy of the early diagnosis of DN. Key words: Cystatin C;  C reactive protein;  β-2 urine microglobulin;  Diabetic nephropathy