尿胱蛋白酶抑制剂C在糖尿病肾病早期诊断中的价值

Diagnostic value of measuring urinary cystatin C in early diabetic nephropathy

目的 :通过检测糖尿病肾病 (DN)患者不同临床分期尿中胱蛋白酶抑制剂C(CystatinC ,CysC)的含量 ,与同时期尿中白蛋白 (Alb)、β2 微球蛋白 (β2 MG)含量比较 ,探讨CysC在DN早期诊断中的价值 .方法 :用放射免疫法测定尿Alb ,β2 MG ;酶免疫标记法测定尿CysC .结果 :DN患者在 2 4h尿白蛋白排泄率 (UAER)小于 30mg时 ,尿中CysC升高至 (0 .2 8± 0 .0 9)mg/L ,与正常对照组 (0 .15± 0 .0 8)mg/L比较差异非常显著 (P <0 .0 1) ;Alb升高至 (6 .2 2± 1.4 1)mg/L ,与正常对照组(3.5 4± 2 .4 2 )mg/L比较差异显著 (P <0 .0 5 ) .β2 MG升高至(0 .10± 0 .0 4 )mg/L ,与正常对照组 (0 .0 4± 0 .0 3)mg/L比较差异显著 (P <0 .0 5 ) .2 4h尿Alb排泄率在 30～ 30 0mg时 ,尿CysC ,Alb和 β2 MG均显著增高 (P <0 .0 1) .结论 :在DN早期 ,尿CysC ,Alb和 β2 MG的排出量均升高 ,但CysC更显著 .尿CysC可以作为诊断DN早期肾损害的灵敏指标 .

AIM: To investigate the levels of urinary Cystatin C, β 2-microglubin and albumin in different stages of diabetes mellitus and to explore the diagnostic value of urinary Cystatin C in early diabetic nephropathy. METHODS: The urinary albumin andβ 2-microglubin were detected by radioimmunoassay (RIA) and Cystatin C was detected by enzyme immunoassay. RESULTS: With UAER<30 mg 24 h urine-1, the level of urinary Cystatin C(0.28±0.09) mg/L was significantly higher than that in the normal group (0.15± 0.08) mg/L (P<0.01), and the β 2-microglubin (0.10±0.04) mg/L and the albumin (6.22±1.41) mg/L were significant higher than those in the normal group (0.04± 0.03) mg/L and (3.54±2.42) mg/L, (P<0.05). With UAER in 30-300 mg 24 h urine-1, the levels of urinary Cystatin C, β 2-microglubin and albumin increased significantly (P< 0.01). CONCLUSION: The levels of urinary Cystatin C, β 2-microglubin and albumin in diabetes mellitus patients are significant higher than those in the normal group, of which the level of Cystatin C increases significantly at early stage, so the Cystatin C is a sensitive index for the early injure of renal in diabetes mellitus.