尿白蛋白/总蛋白比值判断肾小球和非肾小球性血尿的价值探讨

摘要

目的 探讨使用尿白蛋白(Alb)/总蛋白(TP)比值来判断肾小球和非肾小球血尿的实用价值.方法 收集217例已确诊为肾小球疾病(175例)和非肾小球疾病(42例)的患者新鲜晨尿标本,定量检测尿总蛋白、尿白蛋白、尿β2微球蛋白(p2-MG)、尿N-乙酰-β-氨基葡萄糖苷酶(NAG)、足细胞标志蛋白podocalyxin(PCX)和裂孔隔膜蛋白(NPHS1).根据尿常规蛋白定性结果将标本分成三组:尿蛋白阴性肾性血尿组(尿蛋白定性为-/±且为肾小球性血尿的患者)；尿蛋白阳性肾性血尿组(尿蛋白定性为+～++++且为肾小球性血尿的患者)；非肾性血尿组(非肾小球性血尿的患者).采用受试者工作特征(ROC)曲线分析尿Alb/TP比值的诊断价值.结果 以非肾性血尿组为对照,尿Alb/TP比值对肾小球性血尿组(包括尿蛋白阳性和尿蛋白阴性肾性血尿组)判断尿红细胞来源的ROC曲线下面积(AUC)为0.689;尿Alb/TP比值对尿蛋白阳性肾性血尿组的ROC曲线下面积(AUC)为0.965,以0.4233为Cutoff值,对尿蛋白阳性肾性血尿的诊断灵敏度为0.922、特异性为0.952、阳性预期值0.979、阴性预期值0.833、准确度0.931.对β 2-MG、NAG、PCX和NPHS1的结果统计后发现这些指标对诊断尿红细胞来源方面价值不大.结论 使用尿Alb/TP比值判断肾小球和非肾小球性血尿在尿蛋白阳性的病例中有较强的诊断价值,但并不适用于尿蛋白阴性的病例.%Objective To evaluate the clinic value of urinary albumin-to-total-protein ratio in differentiating glomerular and non-glomerular bleeding.Methods 217 patients with hematuria were recruited in the study,including 175 patients with glomerular diseases and 42 patients with non-glomerular diseases.Urinary protein qualitative test and the ratio of albumin-to-total-protein were determined.Urinary β 2 microglobulin,urinary N-acetylglucosamine polyase (NAG),urinary Podocalyxin and NPHS1 were detected at the same time.The patients were divided into 3 groups according to the urinary protein qualitative result.Group 1:the patients were diagnosed as glomerular diseases and with urinary negatively qualitative result.The qualitative result of urinary protein was-to ±.Group 2:the patients were diagnosed as glomerular diseases and with urinary positively qualitative result.The results of urinary protein were + to 4 +.Group 3:control group,the patients were diagnosed as non-glomerular hematuria.The operating characteristic curve analysis (ROC) were used to evaluate the diagnostic value of albumin-total protein ratio.Results It showed that areas under the curve (AUC) of albumin-total protein ratio was 0.689 for all 3 groups but 0.965 for group 2 and 3.The optimal cutoff values was 0.4233,with sensitivity of 0.922,specificity of 0.952,positive predictive value of 0.979 negative predictive value of 0.833 and total accuracy of 0.931.β 2-MG,NAG,PCX and NPHS1 results statistics found that these indicators were of little value for diagnosis of urinary erythrocyte sources.Conclusion Urinary albumin-total protein ratio has high diagnostic value in differentiating glomerular and non-glomerular diseases in those with positive urinary protein,but no applicable value in those with the urinary negative protein.