Evaluation of 8-hour and 12-hour urine collection for detection of proteinuria in hypertensive women, Shariati hospital, 2004 - 2005

Introduction: Hypertensive disorders are common during pregnancy. Combination of hypertension and proteinuria markedly increase prenatal morbidity and mortality. The gold standard method for proteinuria assessment is 24-hour urine collection. This survey is designed to determine the correlation between protein content of 8-hour and 24-hour urine collections. Methods: This cross-sectional study was conducted on 65 pregnant women with gestational age of over-20 weeks who were admitted for assessment of proteinuria in obstetrics section of Shariati hospital, Bandar Abbas. Four urine samples were collected from each patients including random sample, 8, 12 and 24-hour samples. Randoms sample was examined qualitatively while other samples were assessed quantitatively. Data was analyzed by Minitab software. Person's correlation coefficient of 8-hour and 12-hour samples with 24-hour was calculated. Sensitivity, specificity, negative and positive predictive values of random, 8-hour and 12-hour samples were also determined. Results: Pearson&rsquo;s correlation coefficients of 8-hour with 24-hour and 12-hour with 24-hour were 0.873 (P<0.01) and 0.89 (P<0.01), resoectuvely. 8-hour sample had a sensitivity of 63% and negative predictive value of 82%. The 12-hour and random samples predicted significant proteinuria with a sensitivity of 82% and 75%, specificity of 88% and 63%, positive predictive values of 85% and 62%, and negative predictive values of 86% and 76%, respectively. All patients with proteinuria in 8-hour and 12-hour samples had significant proteinuria in 24-hour sample. Conclusion: There is a strong correlation between 8-hour and 12-hour with 24-hour urine protein levels. Either the simultaneous positive or negative result for proteinuria in 8-hour, 12-hour and random samples is of great significance in documentation or ruling out of proteinuria in 24-hour sample collection.