Significance of serum cystatin C in detecting the impairment of glomerular filtration rate in children with renal diseases

Objectives To evaluate the significance of serum cystatin C in detecting the impairment of glomerular filtration rate (GFR) in children.Methods Serum cystatin C,β2-microglobulin and creatinine clearance rate (Ccr) were determined in 417 children with various renal diseases and the correlation between different parameters and Ccr wasassayed,inaddition,the receiver operating characteristics (ROC) analysis was also performed to access their diagnosticaccuracy.Results Serum CysC and β2MG were significantly higher than serum Cr when the patients had Ccr 80 ml/(min·1.73 m2) in various renal diseases.While significant correlation between 1/CysC and Ccr (r =0.710,P 0.01),1/β2MG and Ccr (r = 0.702,P 0.01),and positive correlation between CysC and β2MG (r = 0.897,P 0.01) was found in the patients with their Ccr 80 ml/(min·1.73 m2).ROC plots showed that the area under the ROC curve of CysC,β2MG,and Cr in detecting the decreasing of GFR were 0.910 ± 0.022,0.894 ± 0.025,and 0.683 ± 0.034,respectively.The difference between the areas under the curve (AUC) for serum CysC and Cr,β2MG and Cr (P 0.05) was statistically significant.Conclusions Serum CysC can early reflect GFR impairment,and play more important role in making laboratory diagnosis of the renal diseases than β2MG and Cr.