Obstet Gynecol Sci.  2013 Jan;56(1):8-14. 10.5468/OGS.2013.56.1.8.

Random urine protein/creatinine ratio readily predicts proteinuria in preeclampsia

• Park JH
• Chung D
• Cho HY
• Kim YH
• Son GH
• Park YW
• Kwon JY

• KMID: 1857180
• DOI: http://doi.org/10.5468/OGS.2013.56.1.8

Abstract

OBJECTIVE
To assess the diagnostic accuracy of random urine protein-creatinine (P/C) ratio for prediction of significant proteinuria in preeclampsia as an alternative to the time-consuming 24-hour urine protein collection.
METHODS
Retrospective record analysis was performed on 140 pregnant women who were admitted with suspicion for preeclampsia from January 2006 to June 2011. Random urine protein and/or 24-hour urine protein levels were assessed and their correlation to random urine P/C ratio and 24-hour urine protein excretion was evaluated.
RESULTS
Out of 140 patients, random urine P/C ratio or/and 24-hour urine protein was performed in 79 patients to evaluate significant proteinuria. Of 79 patients, 46 (58%) underwent both tests whereas in 33 women (42%) 24-hour urine collection was not available due to urgent delivery. In 39 cases (85%), significant proteinuria (> or =300 mg/24 hr) was detected with 6 cases (13%) having values over 5,000 mg/24 hr, corresponding to the diagnosis of severe preeclampsia. Random urine P/C ratio highly correlated with 24-hour urine protein excretion (r=0.823, P<0.01). The optimal random urine P/C ratio cutoff points were 0.63 and 4.68 for 300 mg/24 hr and 5,000 mg/24 hr of protein excretion, respectively. with each sensitivity, specificity, and positive and negative predictive values of 87.1%, 100%, 100%, and 58.3%; and 100%, 85%, 50%, and 100%, for significant and severe preeclampsia, respectively.
CONCLUSION
Random urine P/C ratio is a reliable indicator of significant proteinuria in preeclampsia and may be better at providing earlier diagnostic information than the 24-hour urine protein excretion with more accuracy than the urinary dipstick test.

Keyword

Preeclampsia; 24-hour urine protein; Protein-creatinine ratio

MeSH Terms

Female
Humans
Pre-Eclampsia
Pregnant Women
Proteinuria
Retrospective Studies
Sensitivity and Specificity
Urine Specimen Collection

Figure

• 

  Fig. 1 Receiver operating characteristic (ROC) curves. (A) ROC curves for ≥300 mg per 24-hours urine samples (AUC, 0.958; 95% CI, 0.903 to 1.000). (B) ROC curves for ≥5,000 mg per 24-hours urine samples (AUC, 0.921; 95% CI, 1.074 to 2.002). (C) Comparison of ROC curve of ≥300 mg per 24-hours urine collection to urinary dipstick test (AUC, 0.958; 95% CI, 0.903 to 1.000) and 0.935 (95% CI, 0.883 to 0.899). AUC, area under the curve; UPCR, urine protein-creatinine ratio.

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