尿CystC与尿β2-MG诊断DN早期肾损伤的价值比较

Comparison Between Urine CystC and P2-MG for the Diagnosis of Early Diabetic Nephropathy

【目的】探讨尿胱抑素C（CystC）在早期糖尿病肾病（DN）中的诊断价值。【方法】分析在本科住院或门诊体检的238例2型糖尿病患者临床资料，按24h尿白蛋白含量分为两组：A组（正常白蛋白组）和β组（微量白蛋白组）。A组118例，符合尿微量白蛋白（mALβ）〈30mg／24h，β组120例，符合mALβ30～220mg／24h。检测尿CystC、尿p微球蛋白（β2-MG），比较尿CystC与尿G：-MG诊断早期DN的临床价值。另设健康对照组（C组）210例。【结果】三组各检测指标均为偏态分布，经非参数检验分析，三组间均有统计学差异（P〈0．01）。尿CystC和尿口2-MG与年龄之间的线性回归关系无统计学意义（P〉0．05），尿CystC与尿β2-MG呈正相关（r=0．499，P〈O．01），二者均与24h尿蛋白呈正相关（r-0．239，0．265；P〈0．01）。尿CystC、尿82-MG的ROC曲线下面积分剐为0．645、0．794，95％可信区间分剐是0．577～0．713、0．737～0．850。尿CystC的AUCROC（0．645）〈尿p2-MG的AUCROC（0．794）。【结论】尿CystC、尿口2-MG均为检测早期DN的敏感指标，二者存在正相关关系，与尿p2-MG相比，CystC诊断旱期DN的敏感性低于尿＆-MG．

[Objective] To explore the diagnostic value of urine cystatin C（CystC） in early diabetic ne- phropathy（DN）. [Methods] Clinical data of 238 patients with type 2 diabetes mellitus in our department from January 2011 to October 2011 were analyzed. According to 24-hour urine albumin, all patients were divided in- to group A（normal albuminuria group, n = 118, mALBG30mg/24h） and group B（microalbumin group, n=120, 30-220mg/24h mALB）. Urine CystC and 132-MG were determined by enzyme linked immunosorbent as- say（ELISA）. The value between urine CystC andβ2-MG in the diagnosis of early DN was compared. Other 210 healthy subjects were selected as the control group. [Results] All indices in 3 groups showed skewed dis- tribution. By the analysis of nonparameter test, there were significant differences among 3 groups（ P G0.01）. The linear regression correlation between urine CystC or β2-MG and the age had no statistical significance（ P〈0.05）. Urine CystC was positively related with urine ]32-MG（r=0. 499, P 〈0.01）. Both urine CystC and β2-MG were positively related with 24-hour urine albumin（r=0. 239, 0. 265, P 〈0.01）. The area under ROC curve of urine CystC and β2-MG were 0. 645 and 0.794 respectively, and 95o//oo confidence interval of urine Cys- tC and β2-MG were 0. 577-0. 713 and 0. 737-0. 850, respectively. AUCROC Of urine CysC（0. 645） was less than that of urineβ2MG（0. 794）. [Conclusion]Both urine CystC and β2-MG are sensitive indicators for the di- agnosis of early DN. There is positive correlation between urine CystC and β2-MG. The sensitivity of urine CystC for the diagnosis of early DN is lower than that of urineβ2-MG.