Zhuang X, Feng S H, Chen Y, Mou S, Lin J H
Department of Obstetrics and Gynecology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China.
Department of Nephrology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China.
Zhonghua Fu Chan Ke Za Zhi. 2021 Oct 25;56(10):665-670. doi: 10.3760/cma.j.cn112141-20210427-00238.
To study the cut-off values of urinary microalbumin (mAlb), transferrin (TRF) and α1-microglobulin (α1-MG) during pregnancy in pre-eclampsia (PE) with proteinuria. A total of 210 pregnant women were enrolled in Renji Hospital from January 2016 to December 2019, including 92 (43.8%) cases of PE pregnant women and 118 (56.2%) cases of normal pregnant women. According to the diagnostic test evaluation method, the positive predictive values, negative predictive values and accuracy of non-pregnant cut-off values of urinary mAlb, TRF and α1-MG for the quantitative determination of 24-hour proteinuria were analyzed. The receiver operating characteristic (ROC) curve was applied to determine the optimal cut-point values of urinary mAlb, TRF and α1-MG during pregnancy. (1) The diagnostic study of non-pregnant adults urinary mAlb, TRF and α1-MG cut-off values for the determination of 24-hour proteinuria value: when urinary mAlb was 30.0 mg/L, TRF was 2.5 mg/L, α1-MG was 12.5 mg/L as the cut-off value, the positive predictive values of the corresponding 24-hour proteinuria value≥ 300 mg were 88.1% (89/101), 88.2% (90/102) and 78.9% (75/95), its negative predictive values were 97.2% (106/109), 98.1% (106/108) and 85.2% (98/115), its diagnostic accuracy were 92.9% (195/210), 93.3% (196/210) and 82.4% (173/210), respectively. As the 24-hour proteinuria value≥ 300 mg was the golden standard, there were significant differences between the diagnostic method of the non-pregnant cut-off value of urinary mAlb, TRF and the golden standard (<0.05). There was no significant difference between the diagnostic method of the non-pregnant cut-off value of urinary α1-MG and the golden standard (>0.05). (2) Research on the ROC curve and the optimal cut-point value of urinary mAlb, TRF and α1-MG value: as the 24-hour proteinuria value≥ 300 mg as the criterion, the ROC curve of urinary mAlb, TRF and α1-MG were 0.992, 0.984 and 0.907, respectively. The optimal cut-point values of urinary mAlb, TRF and α1-MG were 86.5 mg/L (Youden index=0.927), 5.5 mg/L (Youden index=0.923), and 15.4 mg/L (Youden index=0.687). (3) The diagnostic study of the optimal cut-point value of urinary mAlb, TRF and α1-MG for the determination of 24-hour proteinuria value: according to the ROC results, when urinary mAlb was 86.5 mg/L, urinary TRF was 5.5 mg/L, and urinary α1-MG was 15.4 mg/L as the cut-off value, the positive predictive values of the corresponding 24-hour proteinuria value≥300 mg were 98.9% (86/87), 95.7% (88/92), 87.7% (71/81), and its negative predictive values were 95.1% (117/123), 96.6% (114/118), 83.7% (108/129), and its accuracy were 96.7% (203/210), 96.2% (202/210), 85.2% (179/210). As the 24-hour proteinuria value≥ 300 mg was the golden standard, there was no significant difference between the diagnostic method of the best cut-off values of urinary mAlb, TRF, α1-MG and the golden standard (>0.05). It is recommended to define the cut-off values of mAlb, TRF and α1-MG as 86.5 mg/L, 5.5 mg/L and 15.4 mg/L, respectively, during pregnancy.
研究子痫前期（PE）合并蛋白尿孕妇孕期尿微量白蛋白（mAlb）、转铁蛋白（TRF）和α1-微球蛋白（α1-MG）的截断值。2016年1月至2019年12月，上海交通大学医学院附属仁济医院共纳入210例孕妇，其中PE孕妇92例（43.8%），正常孕妇118例（56.2%）。根据诊断试验评价方法，分析非孕期尿mAlb、TRF和α1-MG截断值对24小时蛋白尿定量测定的阳性预测值、阴性预测值和准确性。应用受试者工作特征（ROC）曲线确定孕期尿mAlb、TRF和α1-MG的最佳截断点值。（１）非孕期成人尿mAlb、TRF和α1-MG截断值对24小时蛋白尿值的诊断研究：以尿mAlb 30.0 mg/L、TRF 2.5 mg/L、α1-MG 12.5 mg/L为截断值时，对应24小时蛋白尿值≥300 mg的阳性预测值分别为88.1%（89/101）、88.2%（90/102）和78.9%（75/95），阴性预测值分别为97.2%（106/109）、98.1%（106/108）和85.2%（98/115），诊断准确性分别为92.9%（195/210）、93.3%（196/210）和82.4%（173/210）。以24小时蛋白尿值≥300 mg为金标准，尿mAlb、TRF非孕期截断值诊断方法与金标准间差异有统计学意义（<0.05）。尿α1-MG非孕期截断值诊断方法与金标准间差异无统计学意义（>0.05）。（２）尿mAlb、TRF和α1-MG值的ROC曲线及最佳截断点值研究：以24小时蛋白尿值≥300 mg为标准，尿mAlb、TRF和α1-MG的ROC曲线下面积分别为0.992、0.984和0.907。尿mAlb、TRF和α1-MG的最佳截断点值分别为86.5 mg/L（约登指数=0.927）、5.5 mg/L（约登指数=0.923）和15.4 mg/L（约登指数=0.687）。（３）尿mAlb、TRF和α1-MG最佳截断点值对24小时蛋白尿值的诊断研究：根据ROC结果，以尿mAlb 86.5 mg/L、尿TRF 5.5 mg/L和尿α1-MG 15.4 mg/L为截断值时，对应24小时蛋白尿值≥300 mg的阳性预测值分别为98.9%（86/87）、95.７%（８８/９２）、87.7%（71/81），阴性预测值分别为95.1%（117/123）、96.6%（114/118）、83.7%（108/129）。准确性分别为96.７%（203/210）、96.2%（202/210）、85.2%（179/210）。以24小时蛋白尿值≥300 mg为金标准，尿mAlb、TRF、α1-MG最佳截断值诊断方法与金标准间差异无统计学意义（>0.05）。建议孕期mAlb、TRF和α1-MG的截断值分别定义为86.5 mg/L、5.5 mg/L和15.4 mg/L。
