Urinalysis vs urine protein-creatinine ratio to predict significant proteinuria in pregnancy

• Published in: Journal of Perinatology Vol. 28; no. 7; pp. 461 - 467
• Main Authors: Dwyer, B K, Gorman, M, Carroll, I R, Druzin, M
• Format: Journal Article
• Language: English
• Published: New York Nature Publishing Group US 01-07-2008; Nature Publishing Group
• Subjects: Adult; Algorithms; Automation; Care and treatment; Catheters; Childbirth & labor; Comorbidity; Confidence intervals; Creatinine; Creatinine - urine; Diagnosis; Enrollments; Female; Gynecology; Health aspects; Humans; Measurement; Medicine; Medicine & Public Health; Obstetrics; original-article; Pediatric Surgery; Pediatrics; Pre-eclampsia; Pre-Eclampsia - diagnosis; Pre-Eclampsia - urine; Preeclampsia; Pregnancy; Pregnant women; Prospective Studies; Proteins; Proteinuria; Proteinuria - diagnosis; Risk factors; ROC Curve; Urinalysis; Urine; United States; United States > US; urine protein–creatinine ratio; urinalysis; preeclampsia; proteinuria; sensitivity and specificity; pregnancy
• ISSN: 0743-8346; 1476-5543
• DOI: 10.1038/jp.2008.4

Objective:
To compare the urine protein–creatinine ratio with urinalysis to predict significant proteinuria (⩾300 mg per day).
Study Design:
A total of 116 paired spot urine samples and 24-h urine collections were obtained prospectively from women at risk for preeclampsia. Urine protein–creatinine ratio and urinalysis were compared to the 24-h urine collection.
Result:
The urine protein–creatinine ratio had better discriminatory power than urinalysis: the receiver operating characteristic curve had a greater area under the curve, 0.89 (95% confidence interval (CI) 0.83 to 0.95) vs 0.71 (95% CI 0.64 to 0.77,
P
<0.001). When matched for clinically relevant specificity, urine protein–creatinine ratio (cutoff ⩾0.28) is more sensitive than urinalysis (cutoff ⩾1+): 66 vs 41%,
P
=0.001 (with 95 and 100% specificity, respectively). Furthermore, the urine protein–creatinine ratio predicted the absence or presence of proteinuria in 64% of patients; urinalysis predicted this in only 19%.
Conclusion:
The urine protein–creatinine ratio is a better screening test. It provides early information for more patients.