慢性肾功能不全患者1d内不同时间点尿总蛋白/肌酐比值的变化情况分析

Changes of random urine total protein-to-creatinine ratio among chronic renal failure patients in 1 d

目的研究随机尿总蛋白(TP)/肌酐(Cr)比值在1 d中不同时间点的变化情况。方法选择临床建议做24 h尿蛋白检测慢性肾功能不全患者28例,所有患者随机尿内生肌酐清除率(Ccr)均>10 mL/min。在常规收集24 h尿样本时,分段收集随机尿样本(取出1.5 mL,其余倒入24 h尿定量收集的容器内)。检测每份样本的24 h尿及随机尿TP和Cr,并计算出TP/Cr比值。取高、中、低3个浓度的24 h蛋白尿样本各1份重复检测,获得该方法的室内误差值,即批间变异系数(CV)。结果 TP、TP/Cr比值高值、中值和低值的CV均<5%,在临床可接受范围内。28例患者中有11例(40%)患者1 d内随机尿TP/Cr比值波动幅度很小,与24 h TP/Cr比值很接近(P>0.05)。此类患者可用随机尿TP/Cr比值来推测24 h尿蛋白量。另有17例(60%)患者1 d内随机尿TP/Cr比值波动幅度很大,随机尿TP/Cr比值波动与24 h尿TP/Cr比值的实验误差(按临床最大可接受范围计算)引起的波动之间存在明显差异(P<0.05);而且一些患者的随机尿TP/Cr比值会出现极端变化,差异甚至可高达30倍。对这60%的患者用任意一次随机尿TP/Cr比值来推测24 h尿蛋白量很难得到正确结果,即该类患者的随机尿TP/Cr比值不能用于代替24 h尿蛋白检测。部分患者即使24 h尿蛋白水平已明显异常,而多次随机尿中UP及TP/Cr比值却在正常范围内,出现假阴性结果。结论大多数患者1 d中随机尿TP/Cr比值的变化较大,建议在有条件的情况下最好采用24 h尿TP评估肾脏蛋白漏出。

Objective To research the changes of random urine total protein （TP） -to-creatinine （Cr） ratio in 1 d. Methods After being determined for 24 h urine protein, a total of 28 patients with renal inadequacy were enrolled. The endogenous ereatinine clearance rate （Ccr） was 〉 10mL/min. When collecting 24 h urine, about 1.5mL urine was taken out at different point as random urine specimen, and the others were put into the 24 h urine specimen quantitation collections. The values of TP, Cr and TP/Cr ratio in random and 24 h urine specimens were detected and calculated. The 24 h urine specimens with high, middle and low protein concentrations were used to analyze laboratory error [ between-run coefficient of variation （CV） ]. Results The CV of TP and TP/Cr ratio with high, middle and low protein concentrations were 〈 5% in the clinical acceptable range. In 11 of 28 （40%） patients, the differentiation between the random urine TP/Cr ratio and 24 h urine TP/Cr ratio wasn＇t significant in statistics （P 〉0.05）. The 24 h urine protein can he calculated by random urine TP/Cr ratio. After calculating the maximum clinical acceptable range, there were 17 （60%） patients whose TP/Cr ratio having a significant differentiation between the random urine TP/Cr ratio and 24 h urine TP/Cr ratio in statistics （ P 〈 0.05 ）. The patients whose TP/Cr ratio of random urine specimens in 1 d had a highly significant differentiation, evenly reached 30 folds. It was hard to get right amount of 24 h urine protein through predicting random urine TP/Cr ratio. The determination of 24 h urine protein can not be replaced by random urine TP/Cr ratio, To many patients, the urine protein and TP/Cr ratio in random urine specimens showed negative results in some points, although the results of 24 h urine protein were abnormal obviously. Conclusions These results show that random urine TP/Cr ratio in 1 d has significant changes for many patients. Therefore ,24 h TP should be used as an alternative to analyze renal protein.