Spot Protein/Creatinine Ratio in Preeclampsia as an Alternative for 24-Hour Urine Protein

Abstract

Background: Proteinuria is a major component of preeclampsia. Urine protein measurement after 24-hour urine collection is the traditional standard method for the detection of proteinuria. It is timeconsuming. As an alternative, random spot sampling for a urine protein to creatinine (P/C) ratio has been investigated. Aims: The aim of the study was to determine the diagnostic accuracy of the protein to creatinine ratio (P/C) compared with 24-hour urine collection for the detection of remarkable proteinuria and to evaluate the P/C ratio for different proteinuria ranges in patients with preeclampsia. Study Design: Case-control study. Methods: Two hundred and eleven pregnant women who met the criteria of preeclampsia comprised the study group and fifty three pregnant women were taken as the control group. Spot urine specimens for measuring P/C ratio were obtained taken immediately before 24-hour urine collection. The correlation between the P/C ratio in the spot urine samples and urinary protein excretion in the 24-hour collections was examined using the Spearman correlation test. Results: It was found a good positive correlation between the P/C ratio and 24-hour protein excretion, with a correlation coefficient (r) of 0.758. The best cut-off which gave the maximum area under the curve was 0.45 for 300 mg, 0.9 for 1000 mg, 1.16 for 2000 mg, 1.49 for 3000 mg, 2.28 for 4000 mg and 2.63 for 5000 mg per 24h. A P/C ratio above 0.9 strongly predicts significant proteinuria for more than 1 gram (AUC 0.97, 95% CI: 0.94-0.99 and sensitivity, specificity, positive and negative predictive value of 91%, 95.4%, 95.2%, and 91.2%, respectively). Conclusion:The P/C ratio can be used as a screening test as a good predictor for remarkable proteinuria. The P/C ratio seems to be highly predictive for diagnosis to detect proteinuria over one gram and it could be used as a rapid alternative test in preeclamptic patients not to delay implementation treatment. Keywords: Preeclampsia, proteinuria, urine proteincreatinine ratio : 27.05.2014 Accepted: 26.11.2014 • DOI: 10.5152/balkanmedj.2015 Increased rate of maternal and fetal mortality and morbidity(1, 2) is associated with preeclampsia. Proteinuria is a main component of preeclampsia and one of the diagnostic criteria of its severity. Protein measurement in the 24-hour urine sample is the traditional standard method for the detection of proteinuria (3). Twenty-four-hour urine collection is timeconsuming and inconvenient, and results may be inaccurate when the collection of urine is missed, depending upon the individual. The management of patients may be delayed during the urine collection. A more rapid test that enables the accurate

Spot urine protein‐to‐creatinine ratio as a diagnostic test in pre‐eclampsia: A gold standard?

“…3 Furthermore, its collection is time-consuming and cumbersome for patients and nursing staff, leading to inaccurate collections and false results in 13%-54% of the analyses, as concluded by Côté et al 4 In obstetric practice nowadays, the PCR is already used in multiple countries to diagnose significant proteinuria when pre-eclampsia is sus- These recommendations are based on numerous studies suggesting that the PCR is a good alternative to the 24HP in pre-eclampsia. [9][10][11][12][13][14][15][16][17][18][19][20] There is still controversy with some studies concluding that, on the contrary, it is not a proper diagnostic test, because of poor sensitivity and specificity 21 or poor correlation with the 24HP due to the variety of results of the PCR over a 24-hour period. 22 Other studies determined that a PCR can be used but only as a "rule-out" test (as the AUC is too low when comparing the PCR to the 24HP) 23 or to assess the magnitude of proteinuria, especially in severe pre-eclampsia, 18 even if the rate of the PCR does not seem to be predictive of adverse pregnancy outcome.…”

Evaluation of spot urinary albumin - creatinine ratio as a screening tool in the prediction of pre-eclampsia in early pregnancy: a pilot study

“…Eigbefoh et al, showed that there is a strong correlation between random urinary protein-to-creatinine ratio and quantitation of 24-hour proteinuria with sensitivity of 92% specificity for the protein/creatinine ratio was 86%. [15][16][17] Sami Jan et al, concluded that spot urine protein to creatinine ratio is an accurate, reliable and steady fast, time saving test which can be used as an alternative method for evaluation of proteinuria in pregnancy induced hypertension and it can substitute 24 hours urinary protein excretion estimation in clinical practice. 18 A cross sectional study of 920 hospitalized patients with suspicion of preeclampsia, Mishra et al, concluded that spot UPCR can be used as a reasonable alternative to 24 hours urine protein estimation with a sensitivity and specificity of 98.1% and 98.6% positive predictive value and negative predictive value 97.4% and 99.2%.…”

Clinico-Demographic Profiles and Urinary Albumin in Prediction of Preeclampsia among Pregnant Women at a Tertiary Care Hospital

“…Other factors that might have been relevant but were not assessed included women's level of activity before the urine was collected. Although 24-h collection of urine is the gold standard for quantifying urinary albumin, a spot urinary albumin-to-creatinine ratio was used in this study because it was more likely to reflect clinical practice for a screening test, and because an attempted 24-h collection would very likely had been futile and erroneous (Demirci et al, 2015). Some of the past studies have shown excellent correlation between spot urinary albumin-to-creatinine ratio and albumin excretion in 24-h urine sample in normal pregnancy and preeclampsia (Morris et al, 2012).…”