Diagnostic value of the test of protein to creatinine ratio in random urine in pregnant women with hypertension for diagnosis of preeclampsia

Document Type : Original Article

Authors

1 Associate Professor, Department of Obstetrics and Gynecology, Women's Health Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

2 General Physician, Women's Health Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

3 Assistant Professor, Department of Community Medicine, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

Abstract

Introduction: Preeclampsia is one of the most common complications of pregnancy and oneof the main causes of maternal and neonatal mortality and morbidity. Excretion of protein in urine is the most important diagnostic sign of diagnosis of the patients with preeclampsia. Current gold standard test for quantitative evaluation of proteinuria is 24 hours urine collection, but, this is a time-consuming and cumbersome method, and using a method which can show urine protein as soon as possible could be effective in proceeding the treatment process. This study was performed with the aim to predict the proteinuria in patients suspected to preeclampsia with using the protein to creatinine ratio in random urine sample and determining the best cut off point.
Methods: This cross-sectional, analytical study was performed on 103 pregnant women with gestational age >20 weeks referred to Emam Reza hospital complaining of BP≥140/90 mmHg or severe edema from 2013-2014. To measure the protein/creatinine ratio, a random urine sample was taken and then 24 hours urine collection was performed for determination of protein excretion. Data analysis was performed by SPSS software (version 16), and Chi-square, T-test, Man-Whitney and logistic regression PResults:  Among 103 pregnant women, protein excretion in 24-h urine was > 300mg in 53 cases and ≤ 300mg in 50 cases. The best cut off point for protein/creatinine ratio of random urine sample was obtained 0.27 with 96% sensitivity and 54% specificity and 70% positive predictive value and 96% negative predictive value (P<0.0001). 
Conclusion: Protein/creatinine ratio of random urine sample could be used as a simple and rapid test to rule out proteinuria in 93% of patients suspected to preeclampsia.

Keywords


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