Abstract
Objective
The predictive value of spot urine protein-to-creatinine ratio (PCR) for estimating
total 24-hour proteinuria in severe preeclampsia is unclear. This study aimed to assess
the diagnostic accuracy of spot urine PCR for ascertaining the magnitude of proteinuria
in women with preeclampsia of varying severity.
Methods
A total of 205 patients with prediagnosed preeclampsia were included in this prospective
cohort study. Patients were allocated into one of the three groups categorized by
severity of disease, as follows: gestational hypertension, group 1 (n = 41); preeclampsia,
group 2 (n = 88); and severe preeclampsia, group 3 (n = 76). We assessed the spot
urine PCRs to determine significant proteinuria and the magnitude of proteinuria in
these groups.
Results
The spot urine PCR was 0.53, with 81% sensitivity and 93% specificity to detect significant
proteinuria. A significant correlation was found between PCR and 24-hour total proteinuria
in group 1 (r = 0.473, P = 0.002). There were also significant correlations in group 2 (r = 0.814, P < 0.001) and group 3 (r = 0.912, P < 0.001). The established formula using spot urine PCR to estimate 24-hour total
proteinuria in severe preeclampsia was Y = 832.02X + 378.74 mg (r2 = 0.8304).
Conclusion
Although 24-hour urine collection remains a merely reliable test to determine the
degree of total proteinuria, our findings suggest that it is likely to assess the
magnitude of proteinuria by the spot urine PCR, especially in severe preeclampsia.
Clinical trial registration
www.clinicaltrials.gov NCT01623791
Résumé
Objectifs
On ne connaît pas exactement la valeur prédictive du rapport protéinurie/créatininurie
(RPC) d'une miction isolée pour estimer la protéinurie sur 24 heures en cas de prééclampsie
grave. Cette étude visait donc à évaluer la précision diagnostique de cette méthode
pour évaluer l'importance de la protéinurie chez des femmes atteintes de prééclampsie
à divers degrés de gravité.
Méthodologie
Nous avons mené une étude de cohorte prospective auprès de 205 patientes ayant déjà
reçu un diagnostic de prééclampsie. Les patientes ont été réparties dans trois groupes
selon la gravité de leur état : hypertension gravidique (groupe 1; n = 41); prééclampsie
(groupe 2; n = 88); prééclampsie grave (groupe 3; n = 76). Nous avons ensuite évalué
le RPC de mictions isolées afin de détecter les cas de protéinurie marquée et de déterminer
l'importance de la protéinurie.
Résultats
Nous avons utilisé une valeur de RPC de mictions isolées de 0,53; la sensibilité et
la spécificité pour la détection d'une protéinurie marquée étaient respectivement
de 81 % et de 93 %. Nous avons observé une corrélation significative entre le RPC
et la protéinurie totale sur 24 heures dans le groupe 1 (r = 0,473; P = 0,002), le groupe 2 (r = 0,814; P < 0,001) et le groupe 3 (r = 0,912; P < 0,001). La formule établie pour estimer la protéinurie sur 24 heures à partir du
RPC d'une miction isolée chez les cas de prééclampsie grave était la suivante : Y = 832,02X +
378,74 mg (r2 = 0,8304).
Conclusion
Bien que la collecte d'urine sur 24 heures demeure d'une certaine fiabilité pour déterminer
le degré de protéinurie totale, nos résultats indiquent qu'il serait possible d'évaluer
l'importance de la protéinurie à l'aide du RPC d'une miction isolée, plus particulièrement
dans les cas de prééclampsie grave.
Clinical trial registration
www.clinicaltrials.gov NCT01623791
Key Words
Abbreviations:
AUC (area under the curve), PCR (protein-to-creatinine ratio), ROC (receiver operating characteristic)To read this article in full you will need to make a payment
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Article info
Publication history
Published online: June 21, 2017
Accepted:
April 13,
2017
Received:
January 11,
2017
Footnotes
Competing interests: None declared.
Identification
Copyright
© 2017 The Society of Obstetricians and Gynaecologists of Canada/La Société des obstétriciens et gynécologues du Canada. Published by Elsevier Inc. All rights reserved.
