Durnwald Celeste, Mercer Brian
Department of Obstetrics and Gynecology, MetroHealth Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA.
Am J Obstet Gynecol. 2003 Sep;189(3):848-52. doi: 10.1067/s0002-9378(03)00849-4.
The purpose of this study was to determine the value of the protein/creatinine ratio in prediction of 24-hour urine total protein among women with suspected preeclampsia.
Women who were evaluated for suspected preeclampsia at >or=24 weeks of gestation were studied prospectively if there was no concurrent diagnosis of chronic hypertension, diabetes mellitus, or preexisting renal disease. A protein/creatinine ratio was obtained, which was followed by the initiation of a 24-hour urine evaluation. Positive and negative predictive values and sensitivity and specificity of the protein/creatinine ratio for significant (>or=300 mg) and severe proteinuria (>or=5000 mg) that were based on 24-hour urine total protein were calculated.
A total of 220 women were evaluated; 43.2% of the women were black, and 80% of the women had government insurance. Mean maternal and gestational ages were 26.1 years and 36.5 weeks, respectively. Significant and severe proteinuria on 24-hour urine evaluation were identified in 76.4% and 8.2% of cases, respectively. Regression analysis of protein/creatinine ratio and 24-hour urine total protein level showed a poor correlation (r(2)=0.41). Receiver operator characteristic analysis revealed an area under the curve of 0.80, but the shoulder value of 390 mg/g carried a high false-negative rate (45.2%). With a more conservative cutoff value, a protein/creatinine ratio of >or=300 mg/g had a poor negative predictive value (47.5%), a specificity for significant proteinuria (55.8%), with a positive predictive value of 85.5%, and a sensitivity of 81%. For severe proteinuria, a protein/creatinine ratio of >or=5000 mg/g had a poor positive predictive value (61.9%) and sensitivity (72.2%), with a negative predictive value of 97.5%, and a specificity of 96.0%.
Protein/creatinine ratio does not exclude adequately the presence of significant proteinuria or predict severe proteinuria and should not be used as an alternative to 24-hour total protein evaluation.
本研究旨在确定蛋白质/肌酐比值在预测疑似子痫前期女性24小时尿总蛋白中的价值。
如果没有同时诊断为慢性高血压、糖尿病或既往肾病，对妊娠≥24周时因疑似子痫前期接受评估的女性进行前瞻性研究。获取蛋白质/肌酐比值，随后开始进行24小时尿液评估。计算基于24小时尿总蛋白的蛋白质/肌酐比值对显著蛋白尿（≥300mg）和严重蛋白尿（≥5000mg）的阳性和阴性预测值以及敏感性和特异性。
共评估了220名女性；43.2%为黑人女性，80%有政府保险。产妇平均年龄和孕周分别为26.1岁和36.5周。24小时尿液评估中，分别有76.4%和8.2%的病例出现显著蛋白尿和严重蛋白尿。蛋白质/肌酐比值与24小时尿总蛋白水平的回归分析显示相关性较差（r² = 0.41）。受试者工作特征分析显示曲线下面积为0.80，但390mg/g的界值假阴性率较高（45.2%）。采用更保守的界值，蛋白质/肌酐比值≥300mg/g的阴性预测值较差（47.5%），显著蛋白尿的特异性为（55.8%），阳性预测值为85.5%，敏感性为81%。对于严重蛋白尿，蛋白质/肌酐比值≥5000mg/g的阳性预测值较差（61.9%）和敏感性（72.2%），阴性预测值为97.5%，特异性为96.0%。
蛋白质/肌酐比值不能充分排除显著蛋白尿的存在，也不能预测严重蛋白尿，不应作为24小时总蛋白评估的替代方法。
