The importance of urinary protein excretion during conservative management of severe preeclampsia

[Preeclampsia: Guidelines for clinical practice from the French College of Obstetricians and Gynecologists]

OBJECTIVE

To identify strategies to reduce maternal and neonatal morbidity related to preeclampsia.

MATERIAL AND METHODS

The quality of evidence of the literature was assessed following the GRADE® method with questions formulated in the PICO format (Patients, Intervention, Comparison, Outcome) and outcomes defined a priori and classified according to their importance. An extensive bibliographic search was performed on PubMed, Cochrane, EMBASE and Google Scholar databases. The quality of the evidence was assessed (high, moderate, low, very low) and recommendations were formulated as a (i) strong, (ii) weak or (iii) no recommendation. The recommendations were reviewed in two rounds with external reviewers (Delphi survey) to select the consensus recommendations.

RESULTS

Preeclampsia is defined by the association of gestational hypertension (systolic blood pressure≥140mmHg and/or diastolic blood pressure≥90mmHg) and proteinuria≥0.3g/24h or a Proteinuria/Creatininuria ratio≥30mg/mmol occurring after 20 weeks of gestation. Data from the literature do not show any benefit in terms of maternal or perinatal health from implementing a broader definition of preeclampsia. Of the 31 questions, there was agreement between the working group and the external reviewers on 31 (100%). In general population, physical activity during pregnancy should be encouraged to reduce the risk of preeclampsia (Strong recommendation, Quality of the evidence low) but an early screening based on algorithms (Weak recommendation, Quality of the evidence low) or aspirin administration (Weak recommendation, Quality of the evidence very low) is not recommended to reduce maternal and neonatal morbidity related to preeclampsia. In women with preexisting diabetes or hypertension or renal disease, or multiple pregnancy, the level of evidence is insufficient to determine whether aspirin administration during pregnancy is useful to reduce maternal and perinatal morbidity (No recommendation, Quality of the evidence low). In women with a history of vasculo-placental disease, low dose of aspirin (Strong recommendation, Quality of the evidence moderate) at a dosage of 100-160mg per day (Weak recommendation, Quality of the evidence low), ideally before 16 weeks of gestation and not after 20 weeks of gestation (Strong recommendation, Quality of the evidence low) until 36 weeks of gestation (Weak recommendation, Quality of the evidence very low) is recommended. In a high-risk population, additional administration of low molecular weight heparin is not recommended (Weak recommendation, Quality of the evidence moderate). In case of preeclampsia (Weak recommendation, Quality of the evidence low) or suspicion of preeclampsia (Weak recommendation, Quality of the evidence moderate, the assessment of PlGF concentration or sFLT-1/PlGF ratio is not routinely recommended) in the only goal to reduce maternal or perinatal morbidity. In women with non-severe preeclampsia antihypertensive agent should be administered orally when the systolic blood pressure is measured between 140 and 159mmHg or diastolic blood pressure is measured between 90 and 109mmHg (Weak recommendation, Quality of the evidence low). In women with non-severe preeclampsia, delivery between 34 and 36+6 weeks of gestation reduces severe maternal hypertension but increases the incidence of moderate prematurity. Taking into account the benefit/risk balance for the mother and the child, it is recommended not to systematically induce birth in women with non-severe preeclampsia between 34 and 36+6 weeks of gestation (Strong recommendation, Quality of evidence high). In women with non-severe preeclampsia diagnosed between 37+0 and 41 weeks of gestation, it is recommended to induce birth to reduce maternal morbidity (Strong recommendation, Low quality of evidence), and to perform a trial of labor in the absence of contraindication (Strong recommendation, Very low quality of evidence). In women with a history of preeclampsia, screening maternal thrombophilia is not recommended (Strong recommendation, Quality of the evidence moderate). Because women with a history of a preeclampsia have an increased lifelong risk of chronic hypertension and cardiovascular complications, they should be informed of the need for medical follow-up to monitor blood pressure and to manage other possible cardiovascular risk factors (Strong recommendation, Quality of the evidence moderate).

CONCLUSION

The purpose of these recommendations was to reassess the definition of preeclampsia, and to determine the strategies to reduce maternal and perinatal morbidity related to preeclampsia, during pregnancy but also after childbirth. They aim to help health professionals in their daily clinical practice to inform or care for patients who have had or have preeclampsia. Synthetic information documents are also offered for professionals and patients.

Twenty-four-hour proteinuria levels are associated with adverse pregnancy outcomes among women with CKD

Background

Proteinuria is commonly measured to assess the renal status of chronic kidney disease (CKD) patients before the 20th week of gestation during pregnancy. High levels of proteiuria have been associated with adverse pregnancy outcomes. However, researchers have not clearly determined what baseline proteinuria levels would be associated with adverse pregnancy outcomes. This study aimed to analyse associations between proteinuria levels and adverse pregnancy outcomes among CKD patients treated with or without steroids/immunosuppressive therapy in early pregnancy.

Methods

This retrospective study included the clinical information of 557 pregnant patients with CKD from 1 January 2009 to 31 December 2021. A multivariable logistic regression analysis was conducted to evaluate the risk of adverse pregnancy outcomes across various proteinuria ranges, which were further stratified by whether the patients were receiving steroids/immunosuppressive therapy.

Results

(i) Proteinuria was assessed on 24-h urine collection. The median (quartile) baseline proteinuria levels were 0.83 g (0.20, 1.92) and 0.25 g (0.06, 0.80) in the steroids/immunosuppressive therapy and therapy-free groups, respectively. (ii) CKD patients with adverse pregnancy outcomes had significantly higher proteinuria levels in the first trimester than patients without adverse pregnancy outcomes. (iii) The risk of adverse pregnancy outcomes increased with increasing baseline proteinuria levels (P < .001). (iv) In the early-pregnancy steroids/immunosuppressive therapy group, the risk of severe preeclampsia was higher in patients with higher baseline proteinuria levels (P < .007) [odds ratio (OR) 30.86 for proteinuria ≥5.00 g/24 h]; in the therapy-free group, the risks of severe preeclampsia, very-low-birth-weight infants, early preterm birth and foetal-neonatal death were higher in patients with higher baseline proteinuria levels (OR 53.16 for proteinuria ≥5.00 g/24 h; OR 37.83 for proteinuria ≥5.00 g/24 h; OR 15.30 for proteinuria ≥5.00 g/24 h; and OR 18.83 for proteinuria ≥5.00 g/24 h, respectively; P < .001, P < .001, P < .001 and P = .006, respectively).

Conclusions

As shown in the present study, a baseline 24-h proteinuria level >1.00 g was associated with adverse maternal outcomes. Furthermore, a 24-h proteinuria level >2.00 g increased the incidence of adverse foetal events among CKD patients.

The association between protein levels in 24-hour urine samples and maternal and neonatal outcomes of pregnant women with preeclampsia

Objective

Hypertensive diseases of pregnancy are one of the leading causes of maternal and perinatal mortality worldwide. The aim of this study was to evaluate the association between protein levels in 24-hour urine samples and maternal and perinatal outcomes in preeclamptic patients.

Material and Methods

This retrospective cohort study was conducted with pregnant women who were diagnosed with preeclampsia (PE) and delivered in our clinic between 2010 and 2018. Patients were divided into those with a proteinuria value below 300 mg/24 h (non-proteinuria), proteinuria value between 300-2000 mg/24 h (mild proteinuria), proteinuria value between 2000-5000 mg/24 h (severe proteinuria) and proteinuria value >5000 mg/24 h (massive proteinuria) and were compared in terms of maternal and perinatal outcomes. Demographic characteristics (age, body mass index in kg/m2, gravidity), PE-related clinical symptoms (epigastric pain, neurological and respiratory symptoms), laboratory findings (24 h protein level, lactate dehydrogenase, aspartate aminotransferase, platelet count and creatine levels) were recorded in all patients.

Results

A total of 1,379 patients meeting the study criteria were included. There were 315 (23%) patients in the non-proteinuria group, 704 (51%) in the mild proteinuria group, 234 (17%) patients in the severe group and 126 (9%) patients in the massive proteinuria group. The massive proteinuria group was found to have the highest rates of maternal and prenatal complications. The Apgar score, umbilical cord pH value, birth weight, gestational week at delivery, intrauterine growth restriction and intrauterine fetal death were significantly higher in the massive proteinuria group.

Conclusion

Our data showed that the degree of proteinuria appears to be associated with maternal, fetal and neonatal outcomes among women diagnosed with PE. Women with proteinuria of >5000 mg/24 hours had notably poorer natal outcomes.

Proteinuria during pregnancy: definition, pathophysiology, methodology, and clinical significance

Qualitative and quantitative measurement of urine protein excretion is one of the most common tests performed during pregnancy. For more than 100 years, proteinuria was necessary for the diagnosis of preeclampsia, but recent guidelines recommend that proteinuria is sufficient but not necessary for the diagnosis. Still, in clinical practice, most patients with gestational hypertension will be diagnosed as having preeclampsia based on the presence of proteinuria. Although the reference standard for measuring urinary protein excretion is a 24-hour urine collection, spot urine protein-to-creatinine ratio is a reasonable "rule-out" test for proteinuria. Urine dipstick screening for proteinuria does not provide any clinical benefit and should not be used to diagnose proteinuria. The classic cutoff cited to define proteinuria during pregnancy is a value of >300 mg/24 hours or a urine protein-to-creatinine ratio of at least 0.3. Using this cutoff, the rate of isolated proteinuria in pregnancy may reach 8%, whereas preeclampsia occurs among 3% to 8% of pregnancies. Although this threshold is widely accepted, its origin is not based on evidence on adverse pregnancy outcomes but rather on expert opinion and results of small studies. After reviewing the available data, the most important factor that influences maternal and neonatal outcome is the severity of blood pressures and presence of end organ damage, rather than the excess protein excretion. Because the management of gestational hypertension and preeclampsia without severe features is almost identical in frequency of surveillance and timing of delivery, the separation into 2 disorders is unnecessary. If the management of women with gestational hypertension with a positive assessment of proteinuria will not change, we believe that urine assessment for proteinuria is unnecessary in women who develop new-onset blood pressure at or after 20 weeks' gestation. Furthermore, we do not recommend repeated measurement of proteinuria for women with preeclampsia, the amount of proteinuria does not seem to be related to poor maternal and neonatal outcomes, and monitoring proteinuria may lead to unindicated preterm deliveries and related neonatal complications. Our current diagnosis of preeclampsia in women with chronic kidney disease may be based on a change in protein excretion, a baseline protein excretion evaluation is critical in certain conditions such as chronic hypertension, diabetes, and autoimmune or other renal disorders. The current definition of superimposed preeclampsia possesses a diagnostic dilemma, and it is unclear whether a change in the baseline proteinuria reflects another systemic disease such as preeclampsia or whether women with chronic disease such as chronic hypertension or diabetes will experience a different "normal" pattern of protein excretion during pregnancy. Finally, limited data are available regarding angiogenic and other biomarkers in women with chronic kidney disease as a potential aid in distinguishing the worsening of baseline chronic kidney disease and chronic hypertension from superimposed preeclampsia.

Chronic hypertension and superimposed preeclampsia: screening and diagnosis

Superimposed preeclampsia complicates about 20% of pregnancies in women with chronic hypertension and is associated with increased maternal and perinatal morbidity compared with preeclampsia alone. Distinguishing superimposed preeclampsia from chronic hypertension can be challenging because, in chronic hypertension, the traditional criteria for the diagnosis of preeclampsia, hypertension, and significant proteinuria can often predate the pregnancy. Furthermore, the prevalence of superimposed preeclampsia is unlikely to be uniformly distributed across this high-risk group but is related to the severity of preexisting endothelial dysfunction. This has led to interest in identifying biomarkers that could help in screening and diagnosis of superimposed preeclampsia and in the stratification of risk in women with chronic hypertension. Elevated levels of uric acid and suppression of other renal biomarkers, such as the renin-angiotensin aldosterone system, have been demonstrated in women with superimposed preeclampsia but perform only modestly in its prediction. In addition, central to the pathogenesis of preeclampsia is a tendency toward an antiangiogenic state thought to be triggered by an impaired placenta and, ultimately, contributing to the endothelial dysfunction pathognomonic of the disease. In the general obstetrical population, angiogenic factors, such as soluble fms-like tyrosine kinase-1 and placental growth factor, have shown promise in the prediction of preeclampsia. However, soluble fms-like tyrosine kinase-1 and placental growth factor are impaired in women with chronic hypertension irrespective of whether they develop superimposed preeclampsia. Therefore, the differences in levels are less discriminatory in the prediction of superimposed preeclampsia compared with the general obstetrical population. Alternative biomarkers to the angiogenic and renal factors include those of endothelial dysfunction. A characteristic of both preeclampsia and chronic hypertension is an exaggerated systemic inflammatory response causing or augmenting endothelial dysfunction. Thus, proinflammatory mediators, such as tumor necrosis factor-α, interleukin-6, cell adhesion molecules, and endothelin, have been investigated for their role in the screening and diagnosis of superimposed preeclampsia in women with chronic hypertension. To date, the existing limited evidence suggests that the differences between those who develop superimposed preeclampsia and those who do not are, as with angiogenic factors, also modest and not clinically useful for the stratification of women with chronic hypertension. Finally, pro-B-type natriuretic peptide is regarded as a sensitive marker of early cardiac dysfunction that, in women with chronic hypertension, may predate the pregnancy. Thus, it has been proposed that pro-B-type natriuretic peptide could give insight as to the ability of women with chronic hypertension to adapt to the hemodynamic requirements of pregnancy and, subsequently, their risk of developing superimposed preeclampsia. Although higher levels of pro-B-type natriuretic peptide have been demonstrated in women with superimposed preeclampsia compared with those without, current evidence suggests that pro-B-type natriuretic peptide is not a predictor for the disease. The objectives of this review are to, first, discuss the current criteria for the diagnosis of superimposed preeclampsia and, second, to summarize the evidence for these potential biomarkers that may assist in the diagnosis of superimposed preeclampsia.

Changes in rate of preterm birth and adverse pregnancy outcomes attributed to preeclampsia after introduction of a refined definition of preeclampsia: A population-based study

INTRODUCTION

Since 2013, various guidelines for hypertension in pregnancy have been refined, no longer requiring proteinuria as a requisite criterion for preeclampsia. We aimed to evaluate the impact of the new definition on preterm birth (PTB) and adverse pregnancy outcomes.

MATERIAL AND METHODS

Women delivering in Ontario between April 2012 and November 2016 were included. Delivery <24+0/7 weeks, major fetal anomalies or preexisting renal disease were excluded. The primary outcome was livebirth <37, <34 or <32 weeks. Rates, adjusted rate ratios (aRR) and ratio of the rate ratio (RRR) were used to compare outcomes in the 2 years after the new Society of Obstetricians and Gynaecologists of Canada (SOGC) guideline (December 2014-November 2016; period 2) vs the 2 years before (April 2012-March 2014; period 1), among women with and without preeclampsia.

RESULTS

In all, 268 543 and 267 964 births in periods 1 & 2, respectively, were included. Respective preeclampsia rates increased significantly from 3.9% to 4.4% (p < 0.001), with no change in maternal morbidity rates. In preeclamptic women, respective rates of PTB <37 weeks were 21.0% and 20.7% (aRR 1.01, 95% confidence interval [CI] 1.00-1.02), with significant aRR for PTB <34 (0.86, 95% CI 0.77-0.96) and <32 weeks (0.79, 95% CI 0.67-0.94). A similar aRR was observed in women without preeclampsia. In preeclamptic women, composite severe neonatal morbidity decreased after guideline change (aRR 0.95, 95% CI 0.91-0.99), a finding not observed in women without preeclampsia (RRR 0.95, 95% CI 0.91-0.99).

CONCLUSIONS

The new definition of preeclampsia was associated with increased disease rates, a modest reduction in adverse neonatal outcomes and no change in maternal outcomes.

Earlier onset of proteinuria or hypertension is a predictor of progression from gestational hypertension or gestational proteinuria to preeclampsia

Although gestational hypertension (GH) is a well-known disorder, gestational proteinuria (GP) has been far less emphasized. According to international criteria, hypertensive disorders of pregnancy include GH but not GP. Previous studies have not revealed the predictors of progression from GP to preeclampsia or those of progression from GH to preeclampsia. We aimed to determine both sets of predictors. A retrospective cohort study was conducted with singleton pregnant women who delivered at 22 gestational weeks or later. Preeclampsia was divided into three types: new onset of hypertension/proteinuria at 20 gestational weeks or later and additional new onset of other symptoms at < 7 days or at ≥ 7 days later. Of 94 women with preeclampsia, 20 exhibited proteinuria before preeclampsia, 14 experienced hypertension before preeclampsia, and 60 exhibited simultaneous new onset of both hypertension and proteinuria before preeclampsia; the outcomes of all types were similar. Of 34 women with presumptive GP, 58.8% developed preeclampsia; this proportion was significantly higher than that of 89 women with presumptive GH who developed preeclampsia (15.7%). According to multivariate logistic regression models, earlier onset of hypertension/proteinuria (before or at 34.7/33.9 gestational weeks) was a predicator for progression from presumptive GH/GP to preeclampsia (odds ratios: 1.21/1.21, P value: 0.0044/0.0477, respectively).

Hypoproteinemia as a parameter of poor perinatal/neonatal outcomes in women with preeclampsia diagnosed as hypertension plus proteinuria

OBJECTIVES

To investigate the relationship between serum total protein (TP) levels and maternal/neonatal outcomes among pregnant women with preeclampsia.

STUDY DESIGN

TP was measured at preeclampsia diagnosis and delivery in 94 women with singleton pregnancies and preeclampsia as hypertension with proteinuria who delivered at ≥ 22 gestational weeks (GWs). As a control group, measurements were also made in 188 women with singleton pregnancies without hypertension and/or proteinuria.

MAIN OUTCOME MEASURES

The relationship between serum TP levels and maternal outcomes.

RESULTS

Serum TP levels showed a significantly negative relationship with urine protein-to-creatinine (P/C) ratio at preeclampsia diagnosis and delivery. Serum TP levels at delivery in the preeclampsia group (53 ± 7 g/L) were lower than in the control group (61 ± 4 g/L, P < 0.0001). In each group, there was no relationship between the daily decrease in TP and the daily increase maternal body weight. However, there was a positive relationship between the daily increase in P/C ratio and the daily increase in maternal body weight in the preeclampsia group (P = 0.0021). Severe hypoproteinemia at preeclampsia diagnosis was a predictor of abruptio placentae (TP < 49 g/L; odds ratio, 21.3) and peripartum cardiomyopathy (TP < 45 g/L; odds ratio, 43.5). Furthermore, women with severe hypoproteinemia at delivery had higher morbidity due to pulmonary edema (TP < 55 g/L; odds ratio, 26.4) and central serous chorioretinopathy (TP < 42 g/L; odds ratio, 264).

CONCLUSIONS

Serum TP levels and proteinuria severity at preeclampsia diagnosis and delivery showed a positive relationship and predicted poor maternal outcome.

Severe proteinuria as a parameter of worse perinatal/neonatal outcomes in women with preeclampsia

OBJECTIVES

The present study aimed to determine the relationship between the severity of proteinuria and maternal/neonatal outcomes among women with preeclampsia.

STUDY DESIGN

Proteinuria severity was measured at preeclampsia diagnosis and at delivery in 94 women with preeclampsia (among 2904 women with singleton pregnancies, who delivered after 22 gestational weeks). Preeclampsia was defined as hypertension with proteinuria.

MAIN OUTCOME MEASURES

Protein:creatinine (P/C) ratio to worse the maternal outcome was 4.8 among women with preeclampsia.

RESULTS

The frequencies of HELLP syndrome and maternal pulmonary edema in women with a P/C ratio ≥5.0 (35.5% and 35.5%, respectively) were significantly higher than those in women with a P/C ratio <5.0 (12.7%, P = 0.014 and 6.4%, P < 0.001, respectively). The best P/C ratio cutoff value to determine early-onset preeclampsia and early preterm birth (EPB) was 4.1 (P < 0.001 and P < 0.001, respectively). The best P/C ratio cutoff values to determine the interval between the preeclampsia diagnosis and delivery <7 days and the need to undergo cesarean section were 1.8 and 1.5, respectively. The best P/C ratio cutoff value to determine maternal pulmonary edema and central serous chorioretinopathy (CSC) was 4.8 (P = 0.020 and P = 0.014, respectively). Finally, the best P/C ratio cutoff values to determine EPB and maternal CSC in women with preeclampsia were 4.1 (odds ratio, 10.9; 95% confidence interval; 4.08 to 29.2, P < 0.0001) and 4.8 (odds ratio, 17.6; 95% confidence interval; 0.898 to 344, P = 0.0008), respectively, according to the multivariate analysis.

CONCLUSIONS

A higher P/C ratio at delivery in women with preeclampsia might cause EPB and CSC.

ACOG Practice Bulletin No. 202: Gestational Hypertension and Preeclampsia

Hypertensive disorders of pregnancy constitute one of the leading causes of maternal and perinatal mortality worldwide. It has been estimated that preeclampsia complicates 2-8% of pregnancies globally (). In Latin America and the Caribbean, hypertensive disorders are responsible for almost 26% of maternal deaths, whereas in Africa and Asia they contribute to 9% of deaths. Although maternal mortality is much lower in high-income countries than in developing countries, 16% of maternal deaths can be attributed to hypertensive disorders (). In the United States, the rate of preeclampsia increased by 25% between 1987 and 2004 (). Moreover, in comparison with women giving birth in 1980, those giving birth in 2003 were at 6.7-fold increased risk of severe preeclampsia (). This complication is costly: one study reported that in 2012 in the United States, the estimated cost of preeclampsia within the first 12 months of delivery was $2.18 billion ($1.03 billion for women and $1.15 billion for infants), which was disproportionately borne by premature births (). This Practice Bulletin will provide guidelines for the diagnosis and management of gestational hypertension and preeclampsia.

Increase in the number of patients diagnosed using the new classification of hypertensive disorders of pregnancy in Japan

AIM

This study aimed to examine how the number of patients diagnosed with pre-eclampsia increased according to the Japanese classification of hypertensive disorders of pregnancy (HDP) that was revised in 2018. The effect of new classification on perinatal outcomes was also analyzed.

METHODS

We enrolled 181 women with HDP who delivered at Hokkaido University Hospital between February 2011 and December 2017. All women were reclassified on the basis of the new classification, in which proteinuria was not required to diagnose pre-eclampsia in patients with maternal organ damage. The number and reasons of reclassification and the admission rate to the neonatal intensive care unit (NICU) and gestational age (GA) at the onset of HDP and at delivery were analyzed.

RESULTS

In this cohort, 17 (9.4%) of 181 women with HDP were reclassified. Low platelet count (41.2%) and uteroplacental dysfunction (41.2%) were the two main causes for reclassification. GA at the onset of HDP (33.6 [29.9-36.1] weeks vs 37.4 [35.7-38.4] weeks; P < 0.001) and at delivery (35.9 [32.4-37.3] weeks vs 38.1 [37.3-39.6] weeks; P < 0.001) were significantly earlier in women with reclassification than women without reclassification. The NICU admission rate was higher in women with reclassification than women without reclassification (70.6% vs 20.4%; P < 0.001).

CONCLUSION

Almost 10% of pregnant women were newly diagnosed with pre-eclampsia as per the new Japanese classification of HDP. Women with reclassification as pre-eclampsia had a greater risk of preterm delivery and NICU admission than those who were not reclassified.

Hypertensive Disorders in Pregnancy

Hypertensive disorders of pregnancy are a heterogeneous group of conditions that include chronic hypertension, gestational hypertension, preeclampsia, and preeclampsia superimposed on chronic hypertension. These disorders account for a significant proportion of perinatal morbidity and mortality nearly 10% of all maternal deaths in the United States. Given the substantial health burden of hypertensive disorders in pregnancy, there is increasing interest in optimizing management of these conditions. This article summarizes the diagnosis and management of each of the disorders in the spectrum of hypertension in pregnancy and highlights recent updates in the field.

Is massive proteinuria associated with maternal and fetal morbidities in preeclampsia?

Objective

The aim of this study was to investigate whether massive proteinuria in preeclampsia is associated with maternal and fetal complications.

Methods

We retrospectively analyzed the clinical records of 233 patients who were diagnosed with preeclampsia. We divided the preeclamptic patients into three groups based on the amount of proteinuria: massive (≥5 g/24 hr), moderate (2 to 5 g/24 hr) and mild (<2 g/24 hr) proteinuria group. We analyzed the clinical characteristics and maternal and neonatal complications among three groups.

Results

Gestational age at diagnosis and delivery were lower in women with massive and moderate proteinuria group than women with mild proteinuria group (31.5±3.1 vs. 32.3±3.6 vs. 34.0±3.5 weeks, P<0.001 for gestational weeks at diagnosis; 34.6±3.6 vs. 35.1±4.1 vs. 36.9±4.0 weeks, P=0.001 for gestational age at delivery). In maternal complications, the incidences of pleural effusion and retinal detachment were significantly different among three groups (29.9% vs. 22.4% vs. 9.0%, P=0.004 for pleural effusion; 11.5% vs. 3.0% vs. 1.3%, P=0.009 for retinal detachment). Creatinine levels were higher and albumin levels were lower in the massive proteinuria group than in the moderate and mild groups. However, other maternal and neonatal complications were not significantly different among three groups.

Conclusion

Massive proteinuria might be associated with renal albumin excretion-related morbidity, such as pleural effusion, retinal detachment, and low serum albumin levels. Furthermore, it was associated with early-onset preeclampsia and early delivery.

Introduction of management protocol for early-onset severe pre-eclampsia

AIM

This quality Improvement study evaluated the applicability of our protocol for early-onset severe pre-eclampsia, prepared in April 2013.

METHODS

We collected data from all women with early-onset severe pre-eclampsia treated at our hospital between March 2008 and August 2015. Neonatal and maternal outcomes were compared between protocol-based (n = 17) and non-protocol-based management groups (n = 28).

RESULTS

The latency period was significantly longer in the protocol-based than in the non-protocol-based group (21.9 ± 3.7 vs 11.0 ± 2.9 days). Gestational age at delivery was significantly more advanced in the protocol-based than in the non-protocol-based group (31.4 ± 0.6 vs 29.8 ± 0.4 weeks). Serious neonatal complications were significantly less prevalent in the protocol-based than in the non-protocol-based group (26% vs 79%). Among the protocol components, magnesium sulfate use was the only independent factor contributing to the absence of serious neonatal complications. The percentages of women exhibiting persistent proteinuria or hypertension at one, two and three months post-partum were similar between the groups.

CONCLUSIONS

Strict adherence to our protocol improved neonatal outcomes without affecting maternal prognosis. Routine use of magnesium sulfate could be the most important component of the protocol.

Pregnancies complicated by preeclampsia and non-preeclampsia-related nephrotic range proteinuria

OBJECTIVE

To examine the impact of nephrotic range proteinuria during pregnancy on renal, maternal and fetal outcomes.

METHODS

A retrospective study of pregnant women with proteinuria greater than 3 g/24 h. Outcome measures included: gestation and mode of delivery, maternal high dependency unit admission, birth weight, maternal blood pressure and proteinuria at time of last follow-up, renal biopsy.

RESULTS

Two hundred and sixty four pregnancies in 262 women were reviewed. Postnatal data were available in 180; of these 104 (57%) had urinary protein quantified postnatally. Sixty three (60%) were pure preeclampsia and nine (9%) super-imposed preeclampsia. Biopsy-proven renal disease was newly diagnosed in nine (9%). Sixty three per cent required caesarean section and 34% required high dependency unit admission. There were no maternal deaths. Birth weight corrected for gestation was below the fifth centile in 33%.

CONCLUSIONS

The incidence of underlying renal pathology in this cohort is significant and highlights the importance of careful follow-up.

Hypertension in pregnancy

Hypertension complicates 5% to 7% of all pregnancies. A subset of preeclampsia, characterized by new-onset hypertension, proteinuria, and multisystem involvement, is responsible for substantial maternal and fetal morbidity and is a marker for future cardiac and metabolic disease. This American Society of Hypertension (ASH) position paper summarizes the clinical spectrum of hypertension in pregnancy, focusing on preeclampsia. Recent research breakthroughs relating to etiology are briefly reviewed. Topics include classification of the different forms of hypertension during pregnancy, and status of the tests available to predict preeclampsia, and strategies to prevent preeclampsia and to manage this serious disease. The use of antihypertensive drugs in pregnancy, and the prevention and treatment of the convulsive phase of preeclampsia, eclampsia, with intravenous MgSO(4) is also highlighted. Of special note, this guideline article, specifically requested, reviewed, and accepted by ASH, includes solicited review advice from the American College of Obstetricians and Gynecologists.

Comparison of outcomes after typical and atypical eclampsia: a retrospective study

OBJECTIVE

To evaluate the characteristics, clinical features and maternal-perinatal outcomes after atypical eclampsia.

METHODS

In a retrospective study, we compared demographics, clinical characteristics and outcomes between typical and atypical eclampsia.

RESULTS

Of 90 eclamptic patients, 56 had typical eclamptic features and 34 had atypical features. Compared to typical eclampsia, atypical eclampsia had higher gestational age (37.6 ± 3.3 vs. 34.6 ± 4.2 weeks, p = 0.001), a higher incidence of no antenatal risk factors [25 (73.5%) vs. 12 (21.4%), p < 0.001], less antepartum seizures [11 (32.4%) vs. 45 (80.4%), p < 0.001], a lower incidence of prodromal symptoms [20 (58.5%) vs. 49 (87.5%), p = 0.002], and a higher incidence of no lesion in brain imaging [16 (47.1%) vs. 12 (21.4%), p = 0.010). Although atypical eclampsia was associated with a lower odd ratio (OR) in composite perinatal complications (OR = 0.22, 95% CI = 0.08-0.60, p = 0.003), composite maternal complications did not differ between the two groups (OR = 0.52, 95% CI = 0.08-0.60, p =0.191).

CONCLUSIONS

Maternal outcomes did not differ between the two groups. Therefore, more attention should be focused on atypical eclampsia.

Etiology and management of postpartum hypertension-preeclampsia

Postpartum hypertension can be related to persistence of gestational hypertension, preeclampsia, or preexisting chronic hypertension, or it could develop de novo postpartum secondary to other causes. There are limited data describing the etiology, differential diagnosis, and management of postpartum hypertension-preeclampsia. The differential diagnosis is extensive, and varies from benign (mild gestational or essential hypertension) to life-threatening such as severe preeclampsia-eclampsia, pheochromocytoma, and cerebrovascular accidents. Therefore, medical providers caring for postpartum women should be educated about continued monitoring of signs and symptoms and prompt management of these women in a timely fashion. Evaluation and management should be performed in a stepwise fashion and may require a multidisciplinary approach that considers predelivery risk factors, time of onset, associated signs/symptoms, and results of selective laboratory and imaging findings. The objective of this review is to increase awareness and to provide a stepwise approach toward the diagnosis and management of women with persistent and/or new-onset hypertension-preeclampsia postpartum period.

Maternal plasma concentrations of angiogenic/anti-angiogenic factors are of prognostic value in patients presenting to the obstetrical triage area with the suspicion of preeclampsia

OBJECTIVE

To determine whether maternal plasma concentrations of placental growth factor (PlGF), soluble endoglin (sEng), soluble vascular endothelial growth factor receptor-1 (sVEGFR-1) and -2 could identify patients at risk for developing preeclampsia (PE) requiring preterm delivery.

STUDY DESIGN

Patients presenting with the diagnosis "rule out PE" to the obstetrical triage area of our hospital at <37 weeks of gestation (n = 87) were included in this study. Delivery outcomes were used to classify patients into four groups: I) patients without PE or those with gestational hypertension (GHTN) or chronic hypertension (CHTN) who subsequently developed PE at term (n = 19); II): mild PE who delivered at term (n = 15); III): mild disease (mild PE, GHTN, CHTN) who subsequently developed severe PE requiring preterm delivery (n = 26); and IV): diagnosis of severe PE (n = 27). Plasma concentrations of PlGF, sEng, sVEGFR-1 and -2 were determined at the time of presentation by ELISA. Reference ranges for analytes were constructed by quantile regression in our laboratory (n = 180; 1046 samples). Comparisons among groups were performed using multiples of the median (MoM) and parametric statistics after log transformation. Receiver operating characteristic curves, logistic regression and survival analysis were employed for analysis.

RESULTS

The mean MoM plasma concentration of PlGF/sVEGFR-1, PlGF/sEng, PlGF, sVEGFR-1 and -2, and sEng in Group III was significantly different from Group II (all p < 0.05). A plasma concentration of PlGF/sVEGFR-1 ≤ 0.05 MoM or PlGF/sEng ≤0.07 MoM had the highest likelihood ratio of a positive test (8.3, 95% CI 2.8-25 and 8.6, 95% CI 2.9-25, respectively), while that of PlGF ≤0.396 MoM had the lowest likelihood ratio of a negative test (0.08, 95% CI 0.03-0.25). The association between low plasma concentrations of PlGF/sVEGFR-1 (≤0.05 MoM) as well as that of PlGF/sEng (≤0.07 MoM) and the development of severe PE remained significant after adjusting for gestational age at presentation, average systolic and diastolic blood pressure, and a history of chronic hypertension [adjusted odds ratio (OR) = 27 (95% CI 6.4-109) and adjusted OR 30 (95% CI 6.9-126), respectively]. Among patients who presented <34 weeks gestation (n = 59), a plasma concentration of PlGF/sVEGFR-1 < 0.033 MoM identified patients who delivered within 2 weeks because of PE with a sensitivity of 93% (25/27) and a specificity of 78% (25/32). This cut-off was associated with a shorter interval-to-delivery due to PE [hazard ratio = 6 (95% CI 2.5-14.6)].

CONCLUSIONS

Plasma concentrations of angiogenic/anti-angiogenic factors are of prognostic value in the obstetrical triage area. These observations support the value of these biomarkers in the clinical setting for the identification of the patient at risk for disease progression requiring preterm delivery.

Evaluation and management of severe preeclampsia before 34 weeks' gestation

OBJECTIVE

We sought to review the risks and benefits of expectant management of severe preeclampsia remote from term, and to provide recommendations for expectant management, maternal and fetal evaluation, treatment, and indications for delivery.

METHODS

Studies were identified through a search of the MEDLINE database for relevant peer-reviewed articles published in the English language from January 1980 through December 2010. Additionally, the Cochrane Library, guidelines by organizations, and studies identified through review of the above documents and review articles were utilized to identify relevant articles. Where reliable data were not available, opinions of respected authorities were used.

RESULTS AND RECOMMENDATIONS

Published randomized trials and observational studies regarding management of severe preeclampsia occurring <34 weeks of gestation suggest that expectant management of selected patients can improve neonatal outcomes but that delivery is often required for worsening maternal or fetal condition. Patients who are not candidates for expectant management include women with eclampsia, pulmonary edema, disseminated intravascular coagulation, renal insufficiency, abruptio placentae, abnormal fetal testing, HELLP syndrome, or persistent symptoms of severe preeclampsia. For women with severe preeclampsia before the limit of viability, expectant management has been associated with frequent maternal morbidity with minimal or no benefits to the newborn. Expectant management of a select group of women with severe preeclampsia occurring <34 weeks' gestation may improve newborn outcomes but requires careful in-hospital maternal and fetal surveillance.

Impact of early chronic kidney disease on maternal and fetal outcomes of pregnancy

BACKGROUND

Elevated serum creatinine is associated with higher maternal and fetal risks; however, the influence of milder degree of renal impairment diagnosed on basis on estimated glomerular filtration rate (eGFR) is less well defined. This study assesses the impact of early chronic kidney disease (CKD) utilizing eGFR in predicting adverse outcomes in women with CKD.

METHODS

We analyzed outcomes of 98 pregnant women with CKD. Women with CKD stage 1 were used as control.

RESULTS

Women with eGFR of 60?89 ml/min were at an increased risk for deterioration of renal function, preeclampsia, and cesarean section. The odd ratios for composite maternal complication of worsening of renal function or preeclampsia were 6.75 (95% confidence interval (CI), 1.84-24.80) in women with eGFR of 60?89. Similarly, women with an eGFR of 60?89 had a significantly increased risk for intrauterine growth restriction (38.5%), preterm birth (31.2%), and intrauterine fetal death (15.8%). The odds for composite fetal adverse outcomes were 2.91 (95% CI, 1.19-7.09) in women with eGFR of 60?89.

CONCLUSIONS

Early CKD increases the risk of adverse outcomes in pregnancy. Estimated GFR ranging between 60?89 ml/min/1.73 m(2) is associated with significant maternal and fetal complications. The risk of adverse outcomes in pregnant women with early CKD can be more accurately stratified by using estimated GFR than the serum creatinine alone.

The kidney in normal pregnancy and preeclampsia

Complicating up to 8% of pregnancies, preeclampsia is, in fact, the most common glomerular disease worldwide. In this article, we review the effect of normal pregnancy on the kidney as well as the role of the kidney in preeclampsia. We discuss blood pressure in pregnancy and preeclampsia, followed by the physiology of hyperfiltration in normal pregnancy as well as the pathophysiology of hypofiltration and proteinuria in preeclampsia. Recent studies have suggested that the clinical syndrome of preeclampsia, which recovers rapidly after delivery of the placenta, is caused by impaired vascular endothelial growth factor signaling that disturbs the status of vascular dilatation as well as the symbiosis between the glomerular endothelium and the podocytes. Finally, we discuss the intriguing association between chronic kidney disease (CKD) and preeclampsia. We hypothesize that the imbalance between angiogenic and anti-angiogenic factors, which may be common to both preeclampsia and CKD, might explain why CKD predisposes pregnant women to develop preeclampsia.

Hypertension in pregnancy

Hypertension complicates 5% to 7% of all pregnancies. A subset of preeclampsia, characterized by new-onset hypertension, proteinuria, and multisystem involvement, is responsible for substantial maternal and fetal morbidity and is a marker for future cardiac and metabolic disease. This American Society of Hypertension (ASH) position paper summarizes the clinical spectrum of hypertension in pregnancy, focusing on preeclampsia. Recent research breakthroughs relating to etiology are briefly reviewed. Topics include classification of the different forms of hypertension during pregnancy, and status of the tests available to predict preeclampsia, and strategies to prevent preeclampsia and to manage this serious disease. The use of antihypertensive drugs in pregnancy, and the prevention and treatment of the convulsive phase of preeclampsia, eclampsia, with intravenous MgSO(4) is also highlighted. Of special note, this guideline article, specifically requested, reviewed, and accepted by ASH, includes solicited review advice from the American College of Obstetricians and Gynecologists.

Outcome of pregnancy in patients with isolated proteinuria

PURPOSE OF REVIEW

The outcome of pregnancy in patients with isolated proteinuria is believed to be favorable. However, whether women with isolated proteinuria are at risk for progressing to preeclampsia has not been extensively studied.

RECENT FINDINGS

The amount of proteinuria is thought to increase in the early third trimester, irrespective of whether preeclampsia has been diagnosed. A dipstick urinalysis has a poor sensitivity (ranging from 22 to 86%) for the detection of significant proteinuria (> or = 0.3 g/day). Measurements of the levels of circulating angiogenic factors such as soluble fms-like tyrosine kinase 1, soluble endoglin, vascular endothelial growth factor, and placental growth factor suggest that gestational proteinuria is a mild variant of preeclampsia. In one study, women with isolated proteinuria (> or = 0.3 g/day) were found to be more likely to progress to preeclampsia than women with isolated hypertension. A considerable number of women with eclampsia exhibited proteinuria alone during their last antenatal visit performed within a week prior to their first convulsion.

SUMMARY

The outcome of women with a retrospective diagnosis of gestational proteinuria is generally favorable. However, a considerable number of women with isolated proteinuria develop hypertension and progress to preeclampsia. Therefore, the statement that the 'outcome of pregnancy in patients with isolated proteinuria is favorable' is misleading. Physicians should be aware of this type of preeclampsia when counseling patients. One possible explanation for the difficulty in diagnosing this form of preeclampsia might be the low sensitivity of the dipstick urinalysis technique for the detection of significant proteinuria.

Interpreting abnormal proteinuria in pregnancy: the need for a more pathophysiological approach

This review and opinion article focuses on the definitions and meanings of abnormal protein excretion in pregnancy, asking the following questions: Are our tests to determine abnormal proteinuria adequately performed? Are current guidelines for diagnosis of excessive proteinuria, especially when used to identify preeclampsia, supported by adequate data? Can the magnitude of proteinuria be used as a reliable clinical biomarker of the gravity of preeclampsia? Should timed urine collections, primarily 24-hour excretions, be supplanted by the urine protein/creatinine ratio in clinical practice? The answers to most of these questions are: We are not sure, or some guidelines are poorly supported by data and may prove erroneous. We suggest a more physiologic approach to assessment of proteinuria and believe that if clinicians and investigators looked at proteinuria in terms of how the kidney handles protein in health and disease it would lead to a more rational and evidence-based approach to proteinuria in pregnancy. Finally, we recommend that current cutoff for abnormal proteinuria be used to diagnose preeclampsia, but the level of proteinuria should not guide management. Other variables, such as status of blood pressure control, evidence of increasing organ damage in the liver and hematological systems, evidence of falling glomerular filtration rate, and signs of neurological involvement, are more reliable indicators of severity of preeclampsia.

ASH position paper: hypertension in pregnancy

The American Society of Hypertension is publishing a series of Position Papers in their official journals throughout the 2008-2009 years. The following Position Paper originally appeared: JASH. 2008;2(6):484-494. Hypertension complicates 5% to 7% of all pregnancies. A subset of preeclampsia, characterized by new-onset hypertension, proteinuria, and multisystem involvement, is responsible for substantial maternal and fetal morbidity and is a marker for future cardiac and metabolic disease. This American Society of Hypertension, Inc (ASH) position paper summarizes the clinical spectrum of hypertension in pregnancy, focusing on preeclampsia. Recent research breakthroughs relating to etiology are briefly reviewed. Topics include classification of the different forms of hypertension during pregnancy, status of the tests available to predict preeclampsia, and strategies to prevent preeclampsia and to manage this serious disease. The use of antihypertensive drugs in pregnancy, and the prevention and treatment of the convulsive phase of preeclampsia, eclampsia, with intravenous magnesium sulfate is also highlighted. Of special note, this guideline article, specifically requested, reviewed, and accepted by ASH, includes solicited review advice from the American College of Obstetricians and Gynecologists.

A Survey of Canadian Practitioners Regarding Diagnosis and Evaluation of the Hypertensive Disorders of Pregnancy

BACKGROUND

How Canadian practitioners are diagnosing and managing the hypertensive disorders of pregnancy (HDP), particularly in relation to the 1997 recommendations published by the Canadian Hypertension Society (CHS), is not known.

METHODS

A survey, with French and English versions (and covering diagnosis, evaluation, and management of pregnancy hypertension), was mailed to all members of the Society of Obstetricians and Gynaecologists of Canada (SOGC) (N = 1757, including obstetricians, family doctors practicing obstetrics, and midwives). Additionally, internists [i.e., all nephrologists (N = 191) and a random sample of 25% of general internists (N = 450)] registered with the Royal College of Physicians and Surgeons of Canada were sampled. The survey was distributed in two mailings and one reminder card. Data were entered into Microsoft Access, and Graph Pad Prism used to summarize responses [N (%)]. Differences in practice between specialties were examined, with a Bonferonni correction used to calculate a significant p value based on the number of comparisons and alpha of 0.05.

RESULTS

Respondents numbered 1187 (49.5%), with 466 not informative for the purpose of the study (due to retirement, or practices that do not include pregnant women with hypertension). The final analysis included 721 completed surveys. Most (609, 84.5% of) respondents take blood pressure (BP) with women in the sitting position, and use a mercury sphygmomanometer (79%) and the 5th Korotkoff (61%) sound to designate diastolic BP (dBP). To monitor pregnancies complicated by preeclampsia, most clinicians use the proposed laboratory tests of maternal well-being (usually at least once/week), fetal well-being [nonstress test (NST, at least once/week), and ultrasonographic studies (once weekly to every two weeks)]. There is general agreement that women with preeclampsia should be delivered for uncontrolled hypertension, end-organ dysfunction, or fetal compromise (nonreassuring NST, severe oligohydramnios, biophysical profile < 4, estimated fetal weight < 5th centile, and reversed end-diastolic flow by umbilical artery Doppler velocimetry). Less consensus was seen for delivery for preeclampsia at > 34 weeks, mild asymptomatic HELLP syndrome, hyperreflexia, and absent end-diastolic flow by umbilical artery Doppler velocimetry.

INTERPRETATION

This survey has clarified the current state of practice with respect to the diagnosis and evaluation of women with all types of HDP. In particular, we have identified areas of potential variability in BP measurement, and provided data on the feasibility of enrolling women with sub types of preeclampsia into intervention studies aimed at prolonging pregnancy.

Expectant management in pregnancies with severe pre-eclampsia

The main objective of expectant management in women with severe pre-eclampsia (PE) remote from term is to improve neonatal outcome. Maternal conditions, however, may worsen during expectant management. This highlights the importance of balancing the risks between maternal and perinatal outcomes. Traditionally, women with severe PE remote from term are delivered expeditiously, regardless of gestational age. We here have reported several retrospective, case-control, observational, prospective, or randomized trials in which expectant management in women with severe PE was feasible in well-selected patients without prejudicing maternal safety, and we have described our rationale and guidelines for this management.

ASH position paper: hypertension in pregnancy

The American Society of Hypertension is publishing a series of Position Papers in their official journals throughout the 2008-2009 years. The following Position Paper originally appeared: JASH. 2008;2(6):484-494. Hypertension complicates 5% to 7% of all pregnancies. A subset of preeclampsia, characterized by new-onset hypertension, proteinuria, and multisystem involvement, is responsible for substantial maternal and fetal morbidity and is a marker for future cardiac and metabolic disease. This American Society of Hypertension, Inc (ASH) position paper summarizes the clinical spectrum of hypertension in pregnancy, focusing on preeclampsia. Recent research breakthroughs relating to etiology are briefly reviewed. Topics include classification of the different forms of hypertension during pregnancy, status of the tests available to predict preeclampsia, and strategies to prevent preeclampsia and to manage this serious disease. The use of antihypertensive drugs in pregnancy, and the prevention and treatment of the convulsive phase of preeclampsia, eclampsia, with intravenous magnesium sulfate is also highlighted. Of special note, this guideline article, specifically requested, reviewed, and accepted by ASH, includes solicited review advice from the American College of Obstetricians and Gynecologists.

Estimation of proteinuria as a predictor of complications of pre-eclampsia: a systematic review

BACKGROUND

Proteinuria is one of the essential criteria for the clinical diagnosis of pre-eclampsia. Increasing levels of proteinuria is considered to be associated with adverse maternal and fetal outcomes. We aim to determine the accuracy with which the amount of proteinuria predicts maternal and fetal complications in women with pre-eclampsia by systematic quantitative review of test accuracy studies.

METHODS

We conducted electronic searches in MEDLINE (1951 to 2007), EMBASE (1980 to 2007), the Cochrane Library (2007) and the MEDION database to identify relevant articles and hand-search of selected specialist journals and reference lists of articles. There were no language restrictions for any of these searches. Two reviewers independently selected those articles in which the accuracy of proteinuria estimate was evaluated to predict maternal and fetal complications of pre-eclampsia. Data were extracted on study characteristics, quality and accuracy to construct 2 x 2 tables with maternal and fetal complications as reference standards.

RESULTS

Sixteen primary articles with a total of 6749 women met the selection criteria with levels of proteinuria estimated by urine dipstick, 24-hour urine proteinuria or urine protein:creatinine ratio as a predictor of complications of pre-eclampsia. All 10 studies predicting maternal outcomes showed that proteinuria is a poor predictor of maternal complications in women with pre-eclampsia. Seventeen studies used laboratory analysis and eight studies bedside analysis to assess the accuracy of proteinuria in predicting fetal and neonatal complications. Summary likelihood ratios of positive and negative tests for the threshold level of 5 g/24 h were 2.0 (95% CI 1.5, 2.7) and 0.53 (95% CI 0.27, 1) for stillbirths, 1.5 (95% CI 0.94, 2.4) and 0.73 (95% CI 0.39, 1.4) for neonatal deaths and 1.5 (95% 1, 2) and 0.78 (95% 0.64, 0.95) for Neonatal Intensive Care Unit admission.

CONCLUSION

Measure of proteinuria is a poor predictor of either maternal or fetal complications in women with pre-eclampsia.

Diurnal blood pressure variation in the evaluation of early onset severe pre-eclampsia

OBJECTIVE

To study the association between diurnal variation in blood pressure, the mean daily blood pressure and various complications of pregnancy in patients presenting with severe pre-eclampsia before 34 weeks' gestation.

STUDY DESIGN

Forty-four women presenting to a tertiary hospital in South Africa with severe pre-eclampsia between 28 and 34 weeks' gestation were managed expectantly for at least 8 days. We measured maternal blood pressure every 30 min with the pregnancy validated Spacelabs 90209 automated blood pressure monitor for 24h periods on alternative days. The mean 24-h diastolic blood pressure measurement, the mean diastolic blood pressure for daytime and nighttime, the day-night blood pressure difference and the night-day ratio were compared with the occurrence of abruptio placentae, gestational age at delivery, neonatal intensive care unit admission, birth weight, abnormal umbilical artery Doppler FVW and reason for delivery.

RESULTS

One hundred and seventy-six 24-h studies were analyzed. The day-night blood pressure difference decreased with increasing mean diastolic blood pressure (r=-0.323, p<0.0001). A combination of normal mean diastolic blood pressure and normal day-night blood pressure difference was associated with increased gestational age and lower caesarean section rates.

CONCLUSION

The combination of mean diastolic blood pressure and day-night blood pressure difference may be a supplementary measurement of disease severity in early onset severe pre-eclampsia and seems to be of prognostic value.

Diagnostic accuracy of urinary spot protein:creatinine ratio for proteinuria in hypertensive pregnant women: systematic review

OBJECTIVE

To review the spot protein:creatinine ratio and albumin:creatinine ratio as diagnostic tests for significant proteinuria in hypertensive pregnant women.

DESIGN

Systematic review.

DATA SOURCES

Medline and Embase, the Cochrane Library, reference lists, and experts. Review methods Literature search (1980-2007) for articles of the spot protein:creatinine ratio or albumin:creatinine ratio in hypertensive pregnancy, with 24 hour proteinuria as the comparator.

RESULTS

13 studies concerned the spot protein:creatinine ratio (1214 women with primarily gestational hypertension). Nine studies reported sensitivity and specificity for eight cut-off points, median 24 mg/mmol (range 17-57 mg/mmol; 0.15-0.50 mg/mg). Laboratory assays were not well described. Diagnostic test characteristics were recalculated for a cut-off point of 30 mg/mmol. No significant heterogeneity in cut-off points was found between studies over a range of proteinuria. Pooled values gave a sensitivity of 83.6% (95% confidence interval 77.5% to 89.7%), specificity of 76.3% (72.6% to 80.0%), positive likelihood ratio of 3.53 (2.83 to 4.49), and negative likelihood ratio of 0.21 (0.13 to 0.31) (nine studies, 1003 women). Two studies of the spot albumin:creatinine ratio (225 women) found optimal cut-off points of 2 mg/mmol for proteinuria of 0.3 g/day or more and 27 mg/mmol for albuminuria.

CONCLUSION

The spot protein:creatinine ratio is a reasonable "rule-out" test for detecting proteinuria of 0.3 g/day or more in hypertensive pregnancy. Information on use of the albumin:creatinine ratio in these women is insufficient.

Assessment of proteinuria in pregnancy

Urinary spot protein:creatinine ratio can reliably rule out proteinuria in pregnancy

Clinical Significance of Proteinuria in Pregnancy

Urinary protein excretion is considered abnormal in pregnant women when it exceeds 300 mg/24 hours at anytime during gestation, a level that usually correlates with 1+ on urine dipstick. Proteinuria documented before pregnancy or before 20 weeks' gestation suggests preexisting renal disease. The National High Blood Pressure Education Program Working Group recommended that that the diagnosis of proteinuria be based on the 24-hour urine collection. Preeclampsia is the leading diagnosis that must be excluded in all women with proteinuria first identified after 20 weeks of gestation. Given the vasospastic nature of this condition, when it is present, the degree of proteinuria may fluctuate widely from hour-to-hour. Hypertension or proteinuria may be absent in 10-15% of patients with HELLP syndrome and in 38% of patients with eclampsia. The acute onset of proteinuria and worsening hypertension in women with chronic hypertension is suggestive of superimposed preeclampsia, which increases adverse outcomes. However, because proteinuria is not independently predictive of adverse outcome, an exclusive proteinuric criterion as an indication for preterm delivery in preeclampsia should be discouraged.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to state that measurement of urinary protein levels by simple techniques are not sensitive or specific, recall that both hypertension and proteinuria may be absent in patients with preeclampsia, and explain that proteinuria is not predictive of adverse outcomes and that delivery should not be based on protein excretion alone.

Intrapartum late deceleration develops more frequently in pre-eclamptic women with severe proteinuria

AIM

Our purpose was to investigate the effect of proteinuria associated with pre-eclampsia on intrapartum fetal heart rate patterns.

METHODS

A retrospective study was performed involving 79 pregnant women with pre-eclampsia and 19 pregnant women with gestational hypertension (GH). Pre-eclampsia was then classified into two groups according to the degree of proteinuria (> or = or < 3 + dipstick), which was classified as severe urinary protein (UP; n = 35) and mild UP (n = 44) at delivery. Intrapartum fetal heart rate (FHR) monitoring was classified as either no deceleration, moderate variable deceleration, severe variable deceleration (sVD), prolonged deceleration (PD), occasional deceleration or recurrent late deceleration (rLD). We evaluated the prevalence of non-reassuring FHR (sVD, PD or rLD), the prevalence of intrauterine growth restriction (IUGR), and cord blood gas status in the three groups. The prevalence of non-reassuring FHR and cord blood gas status of these three groups was also compared with their prevalence in 65 women with low-risk pregnancies. Multiple logistic regression analysis was performed to determine the association between rLD and maternal-fetal parameters.

RESULTS

Levels of systolic and diastolic blood pressure were similar among the three groups. Severe UP was diagnosed significantly earlier, was associated with significantly lower gestational age, and infants with lighter birth weight (P < 0.05) compared with GH and mild UP. The prevalence of IUGR in severe UP was higher than in GH (54%v. 21%, P < 0.05); however, no differences were found in the prevalence of IUGR between mild and severe UP (43%v. 54%, P = 0.33). The prevalence of non-reassuring FHR in GH was not statistically significant in the low-risk pregnancies (5%v. 9%, P = 0.58). In mild and severe UP, the non-reassuring FHRs were more predominant (30% and 43%, respectively) than in low-risk pregnancies and GH (P < 0.05). The rLD was more common in the group with severe UP and accounted for 40% of all FHR patterns. There was no difference in the incidence of low pH among the groups. However, fetuses in pregnancies involving severe UP were significantly hypoxemic when compared with others. Multiple logistic regression analysis showed that worsening proteinuria (odds ratio [OR], 5.5; 95% confidence interval [CI], 2.4-12.9) and IUGR (OR, 3.8; 95% CI, 1.2-11.5) increased the risk of rLD. Rates of preterm birth at less than 32 weeks (OR, 0.7; 95% CI, 0.2-2.5) and severe hypertension (OR, 0.5; 95% CI, 0.2-1.3) were not significant.

CONCLUSION

In pre-eclampsia, the presence of severe proteinuria is associated with an increased likelihood of rLD.

Urine protein estimation in hypertensive pregnancy: which thresholds and laboratory assay best predict clinical outcome?

OBJECTIVE

To determine what threshold for proteinuria could best predict clinical outcome and whether this threshold could be applied universally to any biochemical assay.

DESIGN

A prospective observational study of hypertensive pregnancies referred for further assessment after in a UK University hospital (n=197). Twenty-four hour urine protein was measured by two different assays [benzethonium chloride assay (BCA) and Bradford assay]. The differences between the two assays were calculated from Receiver Operating Characteristic (ROC) curves. Commonly used thresholds for defining preeclampsia (0.3 and 0.5 g/24 hours) were explored for both assays for the prediction of adverse clinical outcomes (severe hypertension, Birthweight<10th percentile, preterm delivery, and a composite biochemical/haematological derangement).

RESULTS

The two assays are not equivalent. The prevalence of>300 mg/24 hour proteinuria and, hence, the prevalence of preeclampsia differed between the two assays. ROC curve analysis demonstrates that the two assays are similar in terms of overall performance as predictive tests. However the threshold of 300 mg/24 hours performs poorly as a predictor of clinical risk. Likelihood ratios (LR) for the BCA at the 300 mg/L threshold for each clinical outcome do not achieve statistical significance. At the 500 mg/L threshold, the LR+for the BCA assay does achieve statistical significance for severe hypertension (LR+:1.51 95% CI 0.99-2.28) and for birthweight<10th percentile (LR+:1.72 95% CI 1.11-2.66). For the Bradford assay at the 300 mg/24 hour threshold, the LR+does achieve statistical significance for birthweight<10th percentile (LR+:1.71 95% CI 1.41-4.31). However, at the 500 mg/24 hour threshold, the LR+is significant for severe hypertension (LR+:2.15 95% CI 1.07-4.34), birthweight<10th percentile (LR+:2.79 95% CI 1.4-5.54) and biochemical disease (LR+:2.47 95% CI 1.22-5.01).

CONCLUSIONS

This study suggests that thresholds for proteinuria need to be higher (possibly>or=0.5 g/24 hours) and there is the need for a "gold standard" proteinuria assay against which all other measures of quantification can be assessed.

Proteinuria in pre-eclampsia: how much matters?

OBJECTIVE

To determine, in women with proteinuric pre-eclampsia, whether a discriminant value of proteinuria at the time of diagnosis predicts the presence or absence of subsequent adverse maternal and fetal outcomes.

DESIGN

Retrospective cohort study.

SETTING

One teaching hospital and two primary referral hospitals in Sydney, Australia.

SAMPLE

Three hundred and twenty-one pregnant women with proteinuric pre-eclampsia, managed according to a uniform management protocol.

METHODS

All women with the diagnosis of proteinuric pre-eclampsia in the years 1998-2001 were studied. After exclusion of women with pre-eclampsia superimposed on pre-existing hypertension, a twin pair, unavailable spot urine results, 353 women were analysed using logistic regression to determine separately the predictors of any adverse maternal or fetal outcomes at the time of delivery. Receiver operating characteristic (ROC) curves, sensitivity and specificity were then calculated from the data.

MAIN OUTCOME MEASURES

Adverse maternal outcomes: severe maternal hypertension (BP > or = 170/110 mmHg), renal insufficiency, liver disease, cerebral irritation, haematological disturbances. Adverse fetal outcomes: small for gestational age, perinatal mortality.

RESULTS

There were 108 (34%) adverse maternal outcomes and 60 (19%) adverse fetal outcomes including two stillbirths. In multivariate analysis, an adverse maternal outcome was significantly associated with higher spot urine protein/creatinine ratio at diagnosis (P < 0.0001) with an odds ratio (OR) of 1.003 per mg/mmol (95% confidence interval [CI] 1.002-1.004) and with older maternal age (P= 0.014) with OR 1.06 per year (95% CI 1.01-1.11). An increased risk of adverse fetal outcome was associated with higher spot urine protein/creatinine (P= 0.013; OR 1.44 per log [mg/mmol], 95% CI 1.08-1.92), gestation at diagnosis <34 weeks (P < 0.0001; OR 3.60, 95% CI 1.90-6.82) and early pregnancy systolic blood pressure < or =115 mmHg (P= 0.0002; OR 3.41, 95% CI 1.77-6.57). The area under the receiver operating characteristic (ROC) curve was 0.67 for adverse maternal outcomes and 0.72 for adverse fetal outcomes.

CONCLUSIONS

With increasing proteinuria, there is increased risk of adverse maternal and fetal outcomes. Although we did not identify a specific spot protein/creatinine ratio that could be used as a definitive screening value for adverse outcomes, it is possible to utilise data from this study to predict the likelihood of adverse maternal and fetal outcomes. A high spot urine protein/creatinine ratio in pre-eclamptic women of greater than 900 mg/mmol ( approximately 9 g/day), or greater than 500 mg/mmol (approximately 5 g/day) in women over 35 years, is associated with a greatly increased likelihood of adverse maternal outcomes.

Hypertension in pregnancy

The hypertensive diseases of pregnancy commonly refer to a group of disorders whose definitions have changed over time within and among professional organizations. Pre-eclampsia, either mild or severe, is managed best with a policy of delivery at or beyond 37 and 34 weeks' gestation, respectively. Similarly, chronic hypertension,gestational hypertension, and chronic hypertension with superimposed pre-eclampsia are conditions wherein it is difficult to justify expectant management beyond 37 weeks' gestation. The approach to management before these gestational ages is subject to interpretation of a limited body of literature.