尿液混匀程度与24小时尿蛋白定量检测结果的相关性研究

目的：24小时尿蛋白定量是慢性肾脏病诊断、疗效评估的重要指标。本研究旨在探讨尿液标本的混匀程度对该指标的影响。方法：本研究选取30例需完善24小时尿蛋白定量检测的住院患者。患者用5L的集尿桶留取24小时尿液。尿液留取完成后,静置1小时,按体积将尿液三等分,上中下三层分别取样,定义为直接采样组;随后用磁力搅棒器充分混匀尿液标本,再次按上述三等分方法留取尿液标本,定义为混匀采样组。最后,采用广义估计方程比较混匀操作前后和不同采样位置的尿蛋白浓度是否存在差异。结果：纳入研究患者的平均年龄 55.9±12.4岁,其中男性18例。研究表明：直接采样组和混匀采样组的同一层面尿蛋白浓度无统计学差异（Wald检验统计量=0.565,P=0.452）。两组内不同层面的取样标本进行比较,各采样点的尿液蛋白浓度无统计学差异（上层vs下层,Wald检验统计量=0.091,P=0.763;中层vs下层,Wald检验统计量=2.252,P=0.133）。校正年龄、性别、eGFR等协变量后,磁力棒混匀前后和不同的采样层面所获得的尿蛋白浓度均无统计学差异。结论：对于尿蛋白总量而言,规范留取的24小时尿液是一份相对均匀的溶液。总尿液采集完成后,短时间内可直接从原尿液任意层面提取临检标本,且该标本的尿蛋白浓度乘以尿量可反映总体的尿蛋白定量。

Research on the correlation between the mixed intensity of urine and 24-hour urine total protein quantity

Objective: 24-hour urine protein quantification is a meaningful indicator for the diagnosis and efficacy evaluation of chronic kidney disease. The study aims to explore the influence of the mixed degree of urine samples on this indicator.Method: This study selected 30 hospitalized patients who needed to complete 24-hour urine protein quantitative testing. The patient used a 5L unified container to collect urine for 24 hours. After collection, the urine sample was stewed for about 1 hour. Based on volume, the urine sample was divided into three equal parts, and samples from the upper, middle, and lower layers separately, defined as the direct sampling group; then, a magnetic stirrer was applied to thoroughly mix the urine sample, and gather the urine sample again according to the above three-part method, defined as the mixed sampling group. Finally, the generalized estimation equation was used to compare whether there was a difference in urine protein content before and after mixing.Result: The average age of patients included in the study was 55.9 ± 12.4 years, including 18 males. At the same level, there was no statistically significant difference in urine protein concentration between the direct sampling group and the mixed sampling group (W test statistic=0.565, P=0 976). There was no statistically significant difference in the urine protein concentration at each sampling point when comparing samples from different levels within two groups (Upper vs Lower, W test statistic=0.091, P=0.763; Middle vs Lower, W test statistic=2.252, P=0.133). After adjusting for covariates such as age, gender, and eGFR, the above result didn’t change.Conclusion: With standard protocol to collect, the entire 24-hour urine sample is a relatively even-distributed solution. Test specimens from the total urine can be directly extracted from any level of the original urine in a short time, and the urine protein concentration of the specimen multiplied by urine volume can reflect the whole day of urine protein quantification.