The value of cystatin C and urine protein/creatinine ratio detection in predicting early renal damage of children with Henoch-Schnlein purpura

Objective To evaluate the value of combined detection of serum cystatin C (Cys C) and urine protein series in predicting renal damage of childhood Henoch-Schnlein purpura (HSP).Methods Serum Cys C and urine protein series were tested in 46 child HSP patients,using liquid transmission turbidity and immune nephelometry.Urine protein series included transferrin (TRF),NAG /UCr,IGGU /UCr,ALBU /UCr and α1MU/UCr.Meanwhile,serum creatinine,urine and serum urea nitrogen were determined.The results were compared with those of healthy control group.Results The value of serum Cys C and urine protein series in HSP patients were higher than those of control group (4.28±0.36) mg/L vs (0.65±0.43) mg/L for serum Cys C(P 0.01);80.43%(37/46) HSP patients whose routine urinalysis were negative had abnormal tested value of six indexes in complete blood test and urine analysis.The value of serum Cys C had a positive correlation with urine protein series.Conclusion Six indexes in complete blood test and urine analysis including serum Cys C and urine protein series help to reveal early renal damage in HSP patients,whilst negative urinalysis can’t rule out early renal damage.The sensitivity and specificity of serum Cys C are superior to urine protein series.These six indexes are appropriate indicators in diagnosis of early renal injury in childhood HSP patients.