尿蛋白与肌酐比值的测定及临床应用的初步评价

目的 通过观察24h尿蛋白定量（24Up）与随机尿和晨尿蛋白/肌酐比值（UP/Ugcr）的相关性,研究随机尿和晨尿UP/Ugcr代替24Up的可行性.方法 选取肾内科住院病人119例,对其24UP与随机尿及晨尿UP/Ugcr进行相关分析.采用ROC曲线分析确定随机尿UP/Ugcr相对于24UP为1 g及3 g的诊断界点.尿蛋白采用改良双缩脲法进行测定,血尿肌酐采用Jaffe法测定.结果 按肾功能分组分析显示,肌酐清除率（Ccr）＜10 ml/min时,随机尿和晨尿UP/Ugcr比值与24UP两者不相关,Ccr＞10 ml/min时高度相关.随机尿Up/Ugcr相应24UP为1 g及3 g的诊断界点分别为0.94g/gcr及2.61g/gcr时敏感性分别为91.6%和96.2%,特异性分别为85.7%和91.1%.随机尿和晨尿UP/Ugcr之间无统计学差异,相关性好.结论 Ccr＞10 ml/min的肾脏病患者,可以用随机或晨尿UP/Ugcr代替24 UP用于监测尿蛋白排泄的变化.当Ccr＜10 ml/min时,两者相关性较差,无临床应用价值.

Estimation of quantitative proteinuria by use the protein-creatinine ratio in random urine samples

Objective By observing the correlation of protein-creatinine ratio(U_P/U_(gcr)) in spot urine specimens(conclude first morning and random urine specimens) and 24-hour urine protein excretion(24U_P),we evaluated the clinical application of U_P/U_(gcr) in spot urine specimens as a predictor of 24U_P.Methods 24-hour urine collection,first morning and random urine specimens were collected from 119 patients.The correlation between U_P/U_(gcr) in spot urine specimens and 24U_P were analyzed.The cutoff value of U_p/U_(gcr) in random urine specimens for screening urinary protein excretion of 1 g and 3 g in 24U_P by receiver operating characteristic(ROC) curve.The urinary protein was tested by the improved biuret automated assay,the creatinine of blood and urine were tested by Jaffe method.Results For patients with Ccr<10 ml/min,the correlation between 24U_P and the U_P/U_(gcr) in spot urine specimens was not significant,but the correlation was high significant for patients with Ccr>10 ml/min.By ROC curve analysis,the U_P/U_(gcr) of 0.94 g/gcr and 2.61 g/gcr in random urine specimens represent the best threshold to detect 24 Up of 1 g and 3 g,the sensitivity was(91.6%)and 96.2% respectively,and the specificity was 85.7% and 91.1% respectively.There was a good correlation and no significance between U_P/U_(gcr) in first morning and random urine specimens.Conclusion The U_P/U_(gcr) in first morning and random urine specimens could be used as an alternative predictor of quantitation of proteinuria to 24U_P in patients with Ccr>10 ml/min.But when patients with Ccr<10 ml/min,U_P/U_(gcr) was not recommended to use.