Accuracy of serum uric acid in predicting complications of pre-eclampsia: a systematic review

Obstetrical outcomes of women with new-onset isolated proteinuria diagnosed after 24 weeks' gestation

PURPOSE

To assess a possible association between marked proteinuria and the risk of preeclampsia with severe features, as defined by the American College of Obstetricians and Gynecologists.

METHODS

This retrospective study included data recorded at a tertiary university-affiliated hospital between 2017 and 2022. Women at or beyond 24 weeks of gestation with proteinuria (protein levels > 300 mg in a 24 h urine collection) and normal blood pressure during the initial 48 h of admission were included. Obstetrical and neonatal outcomes were compared between women with mild proteinuria (300-1000 mg/24 h) and marked proteinuria (≥ 1000 mg/24 h).

RESULTS

Among the women with marked proteinuria (n = 48) compared to those with mild proteinuria (n = 108), the incidences were higher of preeclampsia (50.0% vs. 22.2%, p = 0.001) and of preeclampsia with severe features (18.8% vs. 2.8%, p < 0.001). In multivariate analysis that adjusted for maternal age, primiparity, multiple pregnancy, uric acid level > 6 mg/dL and aspirin treatment, marked proteinuria was a risk factor for preeclampsia with severe features (adjusted odds ratio [aOR] = 10.2, confidence interval [CI] 95% 1.9-54.0, p = 0.007) and for small-for-gestational-age infants (aOR = 2.4, 95% CI 1.02-5.6, p = 0.001). Among women with marked compared to mild proteinuria, rates were also higher of labor induction (58.3% vs. 25.9%, p < 0.001), indicated preterm delivery (41.7% vs. 25.0%, p = 0.04) and admission to the neonatal intensive care unit (44.1% vs. 25.8%, p = 0.017).

CONCLUSIONS

Women with marked compared to mild isolated proteinuria showed higher risk of developing preeclampsia with severe features and of delivering small-for-gestational-age neonates.

Association of maternal serum uric acid levels with LBW/SGA: a large retrospective cohort study

BACKGROUND

Elevated maternal serum uric acid (UA) levels were associated with adverse perinatal outcomes. This study aimed to examine the association between UA and the risk of low birth weight (LBW) / small for gestational age (SGA).

METHODS

A cohort study of women delivered in Shanghai maternity hospital was included between 2017 and 2021. Electronic medical records were utilized to extract information and antenatal care records. The cut-off value of UA was 360 μmol/L. The outcome was LBW/SGA, with LBW defined as birth weight below 2500 g and SGA indicating birth weight below the 10th percentile of average weight for gestational age. The assessment of SGA was based on the Chinese standard curve for birth weight at various gestational ages. Univariate, multivariate logistic regression models, restricted cubic spline were used in this study, with adjustments made for confounding factors.

RESULTS

Sixty-nine thousand six hundred seventy-four live births and singleton pregnancies were included. The ratio of LBW/SGA was 3.3%/9%. Maternal UA levels were significantly negatively correlated with birth weight. High UA levels were associated with high risk of LBW/SGA, especially in third trimester. In BMI < 25 group, the risk of LBW increased to 2.35-fold (95%CI, 1.66-3.31) in hyperuricemic group (UA > 360 μmol/L). The SGA risk was 1.66-fold (95%CI, 1.37-2.00). Gestational hypertension (GH) with hyperuricemica increased the risk of LBW (aOR = 4.00, 95%CI, 2.01-7.93) and SGA (aOR = 2.63, 95%CI, 1.83-3.78). Preeclampsia (PE) with hyperuricemia increased the risk of LBW (aOR = 1.38, 95%CI, 0.63-3.03) and SGA (aOR = 1.81, 95%CI, 1.18-2.78). In delivery gestational week (DGW) ≥ 37 group, if UA > 360 μmol/L, the incidence of LBW increased to 2.46-fold (95%CI, 1.62, 3.73) and the incidence of SGA increased to 1.52-fold (95%CI, 1.24, 1.87). In DGW < 37 group, if UA > 360 μmol/L, the incidence of LBW increased to 2.70-fold (95%CI, 1.92, 3.80) and the incidence of SGA increased to 2.13-fold(95%CI, 1.50, 3.02).

CONCLUSIONS

The study found an inverse correlation between UA levels and birth weight. High UA levels were associated with increased risk of LBW/SGA, particularly in third trimester. GH or PE complicated by hyperuricemia were found to have significantly higher risk of developing LBW/SGA. This relationship also existed in pregnant women with BMI < 25.

Alteration in maternal serum uric acid levels in pre-eclampsia and associated perinatal outcomes: a cross-sectional study in Ghana

Introduction

pre-eclampsia (PE) is a multisystemic pregnancy-specific hypertensive disorder associated with significant adverse maternal and perinatal outcomes. Maternal serum uric acid level is hypothesized as a reliable marker for predicting the severity and adverse outcomes of pre-eclampsia and facilitating clinical decisions. This study explored the association between maternal serum uric acid and adverse pregnancy outcomes in pre-eclampsia.

Methods

a cross-sectional study involving women diagnosed with pre-eclampsia was conducted at Korle-Bu Teaching Hospital (KBTH), a tertiary hospital in Ghana. Descriptive analyses were performed and multivariable logistic regression model was used to explore the association between maternal serum uric acid levels and pregnancy outcomes using R software.

Results

we included 100 women with pre-eclampsia comprising 79% and 21% preterm and term pre-eclampsia respectively and with mean gestational age (GA) at diagnosis of 32.35±2.66 weeks and 35.96±1.94 weeks respectively. The mean maternal age of preterm and term pre-eclampsia groups was 29.81±5.29 years and 29.46±5.78 years respectively. Hyperuricemia (serum uric acid >375 µmol/L) occurred in 61% of the pre-eclamptic women. The mean gestational age (in weeks) at diagnosis was significantly lower in the pre-eclamptic women with hyperuricemia compared with those with normal levels of uric acid (33.51±3.03 versus 34.80±2.71). There was a significant negative association (moderate correlation) between maternal serum uric acid levels and birth weight (R= -0.34, p < 0.001) in pre-eclampsia; the statistical significance was limited to preterm only (Pearson R= -0.39, p-value <0.001) but not term pre-eclampsia. Hyperuricemia was significantly associated with low birth weight [aOR: 3.222 (95% CI: 1.098, 10.393)], caesarean section [aOR: 2.281 (95% CI: 1.084, 7.568)] and severe diastolic pressure at birth [aOR: 3.517 (95% CI: 1.123, 11.939)].

Conclusion

hyperuricemia in pre-eclampsia was significantly associated with both maternal (caesarean section and severe hypertension) and neonatal (low birth weight) adverse outcomes. Hyperuricemia seems clinically useful in predicting pregnancy outcomes, especially in preterm pre-eclampsia. Further longitudinal study is recommended in exploring the clinical significance of maternal uric acid levels and pregnancy outcomes in pre-eclampsia.

Withstanding the test of time: Morning versus afternoon/evening urine protein-to-creatinine ratios in preeclampsia

OBJECTIVE

There are mixed findings regarding time preference for measuring spot urine protein to creatinine ratios (UPCR) in renal patients but no such literature among pregnant patients. We compare AM versus PM measurements for UPCR among pregnant patients with preeclampsia.

STUDY DESIGN

This retrospective study included 163 patients diagnosed with preeclampsia. Laboratory tests of UPCR, urine specificity gravity, and uric acid were collected for these patients during the morning (AM) 12:00 AM (00:00) through 11:59 AM (11:59) and afternoon/evening (PM) 12:00 PM (12:00) through 11:59 PM (23:59).

MAIN OUTCOME MEASURES

Outcomes were UPCR percentages indicative of preeclampsia, UPCR median values, abnormal uric acid, and normal urine specific gravity indicative of a quality sample for measuring UPCR.

RESULTS

UPCR ≥ 0.3 indicative of preeclampsia significantly differed (p < 0.001) where the AM group (76.7 %) had a greater percentage than the PM group (52.8 %). Median UPCR significantly differed (p < 0.001) where the AM group had a greater median (0.44) than the PM group (0.32). None of the uric acid or urine specific gravity comparisons significantly differed between the AM and PM groups. Similar patterns occurred for subgroups of those with hypertension, nulliparous, and preeclampsia with severe features.

CONCLUSION

We found that UPCR had greater median values and more values indicative of preeclampsia for AM measurements than PM measurements. Clinicians who use spot urine measurements and not 24-hour urine measurements should preferably measure UPCR in the AM rather than the PM.

Longitudinal assessment of angiogenic markers in prediction of adverse outcome in women with confirmed pre-eclampsia

OBJECTIVES

Angiogenic marker assessment, such as the ratio of soluble fms-like tyrosine kinase-1 (sFlt-1) to placental growth factor (PlGF), is known to be a useful tool in the prediction of pre-eclampsia (PE). However, evidence from surveillance strategies in pregnancies with a PE diagnosis is lacking. Therefore, we aimed to assess the predictive performance of longitudinal maternal serum angiogenic marker assessment for both maternal and perinatal adverse outcomes when compared to standard laboratory parameters in pregnancies with confirmed PE.

METHODS

This was a retrospective analysis of prospectively collected data from January 2013 to December 2020 at the Medical University of Vienna. The inclusion criteria were singleton pregnancy with confirmed PE and post-diagnosis maternal serum angiogenic marker assessment at a minimum of two timepoints. The primary outcome was the predictive performance of longitudinal sFlt-1 and PlGF assessment for adverse maternal and perinatal outcomes compared to conventional laboratory monitoring at the same time in pregnancies with confirmed PE. Composite adverse maternal outcome included intensive care unit admission, pulmonary edema, eclampsia and/or death. Composite adverse perinatal outcome included stillbirth, neonatal death, placental abruption, neonatal intensive care unit admission, intraventricular hemorrhage, necrotizing enterocolitis, respiratory distress syndrome and/or mechanical ventilator support.

RESULTS

In total, 885 post-diagnosis sFlt-1/PlGF ratio measurements were obtained from 323 pregnant women with confirmed PE. For composite adverse maternal outcome, the highest standalone predictive accuracy was obtained using maternal serum sFlt-1/PlGF ratio (area under the receiver-operating-characteristics curve (AUC), 0.72 (95% CI, 0.62-0.81)), creatinine (AUC, 0.71 (95% CI, 0.62-0.81)) and lactate dehydrogenase (LDH) levels (AUC, 0.73 (95% CI, 0.65-0.81)). Maternal platelet levels (AUC, 0.65 (95% CI, 0.55-0.74)), serum alanine aminotransferase (ALT) (AUC, 0.59 (95% CI, 0.49-0.69)) and aspartate aminotransferase (AST) (AUC, 0.61 (95% CI, 0.51-0.71) levels had poor standalone predictive accuracy. The best prediction model consisted of a combination of maternal serum LDH, creatinine levels and sFlt-1/PlGF ratio, which had an AUC of 0.77 (95% CI, 0.68-0.85), significantly higher than sFlt-1/PlGF ratio alone (P = 0.037). For composite adverse perinatal outcome, the highest standalone predictive accuracy was obtained using maternal serum sFlt-1/PlGF ratio (AUC, 0.82 (95% CI, 0.75-0.89)) and creatinine (AUC, 0.74 (95% CI, 0.67-0.80)) levels, sFlt-1/PlGF ratio being superior to creatinine alone (P < 0.001). Maternal serum LDH levels (AUC, 0.65 (95% CI, 0.53-0.74)), platelet count (AUC, 0.57 (95% CI, 0.44-0.67)), ALT (AUC, 0.58 (95% CI, 0.48-0.67)) and AST (AUC, 0.58 (95% CI, 0.48-0.67)) levels had poor standalone predictive accuracy. No combination of biomarkers was superior to maternal serum sFlt-1/PlGF ratio alone for prediction of composite adverse perinatal outcome (P > 0.05 for all).

CONCLUSIONS

In pregnancies with confirmed PE, longitudinal maternal serum angiogenic marker assessment is a good predictor of adverse maternal and perinatal outcomes and superior to some conventional laboratory parameters. Further studies should focus on optimal surveillance following diagnosis of PE. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

A Study on Serum Lactate Dehydrogenase and Uric Acid in Preeclampsia and Eclampsia: Can they Predict Adverse Fetomaternal Outcome?

Background

Hypertensive disorders of pregnancy affect 3%-5% of all pregnancies, contributing immensely to maternal morbidity and mortality. According to the WHO, the incidence of deaths due to preeclampsia and eclampsia in developing and developed countries is 2.8% and 0.4%, respectively. Lactate dehydrogenase (LDH) and uric acid are good predictors of disease severity.

Aim

This study aims to determine the fetomaternal outcome in relation to abnormal serum levels of LDH and uric acid.

Materials and Methods

A cross-sectional study was carried out in 1200 patients with preeclampsia and eclampsia at a tertiary care center over 2 years. Patients were divided into - Group A: patients with normal LDH (≤300 IU/L) and uric acid (<6 mg/dl) (n = 300). Group B: patients with abnormal LDH and uric acid (n = 900), who were further divided into mild and severe preeclampsia and eclampsia. Abnormal serum values were stratified into groups for easier comparison. The results were compared in terms of maternal and perinatal outcomes.

Results

The incidence of preeclampsia and eclampsia in our study is 3.14% and 1.57%, respectively. Significant changes in LDH and uric acid were associated with increased severity of the disease (LDH - 1116.94 ± 4.78; uric acid - 9.2 ± 2.89). Higher incidence of maternal and fetal complications was seen with severe preeclampsia and eclampsia with LDH >800 IU/L and uric acid >6 mg/dl.

Conclusion

Standard antenatal follow-up should be carried out for early detection and prevention of preeclampsia, with strict monitoring of serum uric acid level and LDH. This may reduce the maternal and fetal complications due to preeclampsia.

Uric acid and risk of pre-eclampsia: results from a large case-control study and meta-analysis of prospective studies

To quantify the association between maternal uric acid levels and pre-eclampsia risk in a large collection of primigravid women. A case-control study (1365 cases of pre-eclampsia and 1886 normotensive controls) was conducted. Pre-eclampsia was defined as blood pressure ≥ 140/90 mmHg and proteinuria ≥ 300 mg/24 h. Sub-outcome analysis included early, intermediate, and late pre-eclampsia. Multivariable analysis for pre-eclampsia and its sub-outcomes was conducted using binary and multinomial logistic regression, respectively. Additionally, a systematic review and meta-analysis of cohort studies measuring uric acid levels < 20 weeks of gestation was performed to rule out reverse causation. There was a positive linear association between increasing uric acid levels and presence of pre-eclampsia. Adjusted odds ratio of pre-eclampsia was 1.21 (95%CI 1.11-1.33) for every one standard deviation increase in uric acid levels. No differences in the magnitude of association were observed between early and late pre-eclampsia. Three studies with uric acid measured < 20 weeks' gestation were identified, with a pooled OR for pre-eclampsia of 1.46 (95%CI 1.22-1.75) for a top vs. bottom quartile comparison. Maternal uric acid levels are associated with risk of pre-eclampsia. Mendelian randomisation studies would be helpful to further explore the causal role of uric acid in pre-eclampsia.

Hypertensive Disorders of Pregnancy

Hypertensive disorders in pregnancy are a leading cause of global maternal and fetal morbidity. The four hypertensive disorders of pregnancy include chronic hypertension, gestational hypertension, preeclampsia-eclampsia, and chronic hypertension with superimposed preeclampsia. A careful history, review of systems, physical examination, and laboratory analysis can help differentiate these disorders and quantify the severity of the disease, which holds important implications for disease management. This article reviews the different types of disorders of hypertension in pregnancy and how to diagnose and manage these patients, with special attention paid to any recent changes made to this management algorithm.

Role of CA-125 Level as a Marker in the Management of Severe Pre-Eclampsia

BACKGROUND AND OBJECTIVES

Hypertensive disorders of pregnancy remain one of the leading causes of morbidity and mortality in maternal-fetal medicine worldwide, particularly in low-resource settings. Despite extensive research in the last decades, pre-eclampsia prediction and, thus, effective prevention remains an unsolved problem. Current evidence suggests that CA-125, an already recognised tumoral marker and, lately, a valuable severity marker of heart failure, can be used to evaluate pre-eclampsia severity and thus improve the identification and management of high-risk patients; Materials and Methods: This is a case-control study involving 100 pregnant patients over 25 weeks of gestation, grouped based on the severity of hypertension in gestational hypertension (n = 22), non-severe pre-eclampsia (n = 11), severe pre-eclampsia (n = 17), and a control group (normotensive) (n = 50). Clinical and biochemical parameters recommended by the international guidelines for evaluating hypertensive pregnant patients were gathered from every patient in addition to CA-125 levels. The correlation was analysed.

RESULTS

Mean CA-125 levels increased with the severity of hypertension from a mean of 8.97 U/mL (±2.84) in the normotensive group to a mean of 21.23 U/mL (±11.18) in the severe pre-eclampsia group. Significant differences were observed between each group. The correlation of CA-125 levels with the assessed clinical and biochemical parameters showed positive correlations with MAP, 24 h proteinuria, and LDH values and negative correlations with platelet count, gestational age at birth, and birth weight Conclusions: The reported results support this marker's promising role as a severity marker and its potential to improve pre-eclampsia management allowing a better selection of high-risk patients, aiding in decision making related to hospitalisation and/or timing of birth. Further studies are needed to improve the accuracy of the obtained results, identify an accurate cut-off and an optimal time of measurement, and achieve standardisation in measuring the marker.

Maternal serum uric acid, creatinine and blood urea levels in the prediction of pre-eclampsia among pregnant women attending ANC and delivery services at Bahir Dar city public hospitals, northwest Ethiopia: A case-control study

Background

Pre-eclampsia (PE) is a metabolic disorder that adversely affects the lives of mother and their infants. Even though, several studies have been conducted on PE, no effective diagnostic and therapeutic agents were developed so far. Hence, this study was designed to evaluate serum uric acid, blood urea and creatinine levels in the prediction of PE.

Methods

A hospital-based case-control study was conducted among pregnant women. A simple random sampling technique was applied to select study participants. The socio-demographic and clinical data were collected using an interview-administered questionnaire. Serum samples were used to determine the maternal uric acid, urea and creatinine levels via an automated chemistry analyzer. Independent sample t-test, Pearson correlation test and receiver operating characteristic (ROC) curve analysis were performed to check the association and diagnostic accuracy of variables to PE.

Results

The mean ages (in years) of the case and control groups were 27.98 ± 5.64 and 27.33 ± 4.45, respectively. The mean serum uric acid and blood urea levels were significantly higher in pre-eclamptic women than in normotensive pregnant women (6.27 ± 0.20 vs 4.43 ± 0.15, and 8.50 ± 3.99 vs 5.67 ± 2.19), respectively but the serum creatinine level is non-significantly increased in cases as compared to controls (0.70 ± 0.05 vs 0.50 ± 0.01). The areas under the ROC curve of serum uric acid, creatinine and blood urea levels were 0.785, 0.735 and 0.764 (sensitivity: 69%, 60.7%, 67.9%; specificity: 73.8%, 75%, 71.4%) with the cutoff points of ≥5.25 mg/dL, ≥0.565 mg/dL and ≥6.5 mg/dL, respectively.

Conclusion

In this study, we observed a significantly higher concentration of serum uric acid and blood urea values in pre-eclampsia as compared with normotensive pregnant women. Therefore, this suggested that serum uric acid; blood urea and creatinine values can be associated with PE. Moreover, serum uric acid, blood urea and creatinine levels could be carefully utilized as a diagnostic marker for PE, but their inclusion in routine diagnostic test to PE requires large-scale multi-center prospective studies that corroborate our findings.

Relationship between maternal serum uric acid level and preeclampsia with or without severe features

Hyperuricaemia is common in preeclampsia. Its relationship and the utility in predicting of preeclampsia must be evaluated. The objective was to determine the association between maternal serum uric acid level and preeclampsia with or without severe features, including maternal and neonatal outcomes. A retrospective study was conducted at Rajavithi Hospital between June 2015 and May 2019. Inferential analysis comparison using binary logistic regression analysis and correlation using Chi-Square test/Fisher's exact test were used for analysis. Among the 400 participants, 331 (82.7%) women were preeclampsia with severe features. The mean uric acid level was significantly higher in women with preeclampsia with severe features compared to those without (6.44 ± 1.44 vs 5.87 ± 1.53 mg/dL, p-value = .016). Uric acid greater than 7 mg/dL was associated with renal involvement and preeclampsia with severe features. Uric acid 5-7 and greater than 7 mg/dL correlated with preterm birth (OR 2.67, 95% CI 1.59-4.49 and OR 4.89, 95% CI 2.75-8.68, respectively). Uric acid greater than 7 mg/dL also increased the risk of RDS and NICU admission. In conclusion, a high uric acid level is associated with preeclampsia with severe features and adverse pregnancy outcomes and may be the predictor of the severity of preeclampsia.Impact statementWhat is already known on this subject? Hyperuricaemia is a common finding in preeclamptic pregnancy due to reduction of uric acid clearance secondary to reduced glomerular filtration rate, increased reabsorption, and decreased secretion. The correlation of increase maternal uric acid level and preeclampsia including adverse pregnancy outcomes has been evaluated and supported the use of uric acid as a predictor for preeclampsia development. However, its clinical utility is still debateable.What the results of this study add? The present study demonstrated the association between higher maternal serum uric acid level and severity of preeclampsia. Particularly, serum uric acid greater than 7 mg/dL was associated with preeclampsia with severe features. Additionally, serum uric acid level 5-7 mg/dL and greater than 7 mg/dL had a positive correlation with adverse maternal and neonatal outcomes.What the implications are of these findings for clinical practice and/or further research? Maternal serum uric acid may be used as the predictor of severity of preeclampsia. However, the sensitivity and specificity and the precise clinical utility of uric acid related to preeclampsia need to be further evaluated in larger sample size.

Hypertensive Disorders of Pregnancy: Common Clinical Conundrums

Importance

Hypertensive complications of pregnancy comprise 16% of maternal deaths in developed countries and 7.4% of deaths in the United States. Rates of preeclampsia increased 25% from 1987 to 2004, and rates of severe preeclampsia have increased 6.7-fold between 1980 and 2003.

Objective

The aim of this study was to review current and available evidence for common clinical questions regarding the management of hypertensive disorders of pregnancy.

Evidence Acquisition

Original research articles, review articles, and guidelines on hypertension in pregnancy were reviewed.

Results

Severe gestational hypertension should be managed as preeclampsia with severe features. Serum uric acid levels can be useful in predicting development of superimposed preeclampsia for women with chronic hypertension. When presenting with preeclampsia with severe features before 34 weeks, expectant management should be considered only when both maternal and fetal conditions are stable. In the setting of hypertensive disorders of pregnancy, oral antihypertensive medications should be initiated when systolic blood pressure is greater than 160 mm Hg or when diastolic blood pressure is greater than 110 mm Hg, with the most ideal agents being labetalol or nifedipine. Furthermore, although risk of preeclampsia recurrence in future pregnancy is low, women with a history of preeclampsia should be managed with 81 mg aspirin daily for preeclampsia prevention.

Conclusions and Relevance

Despite the frequency with which hypertensive disorders of pregnancy are encountered clinically, situations arise frequently with limited evidence to guide providers in their management. An urgent need exists to better understand this disease to optimize outcomes for impacted patients.

Role of derived neutrophil-to-lymphocyte ratio, uric acid-to-creatinine ratio and Delta neutrophil index for predicting neonatal outcomes in pregnancies with preeclampsia

We aimed to compare the maternal and neonatal systemic inflammatory markers, platelet indices and new indices in biochemical parameters in women with preeclampsia and healthy controls. The secondary aim was to investigate whether there was a relationship between maternal hematological markers and neonatal outcomes. A retrospective case control study was conducted in a tertiary hospital. Maternal demographic and birth characteristics, complete blood count indices, derived neutrophil to lymphocyte ratio (dNLR), Delta neutrophil index (DNI), uric acid-to-creatinine (Cre) ratio and uric acid-to-alanine transaminase ratio, neonatal hematological parameters were compared between the preeclamptic group and control group. The study consisted of 170 cases (84 preeclampsia and 86 control). Neutrophil-to-lymphocyte ratio (NLR), dNLR, blood urea nitrogen (BUN), creatinine (Cre), uric acid, LDH, aspartate transaminase (AST) and alanine aminotransferase (ALT), uric acid-to-Cre ratio and uric acid-to-ALT ratio were higher and statistically significant in the preeclamptic group than in control ones (p: 0.000 - BUN, Cre, uric acid, LDH, p: 0.001 - AST, p: 0.004 - ALT, p: 0.000 - uric acid-to-Cre ratio, p: 0.009 - uric acid-to-ALT ratio, respectively). NLR and platelet-to-lymphocyte (PLR) ratio were significantly higher in newborns of preeclamptic mothers (p: 0.039; p: 0.004, respectively). A low-moderate correlation between maternal uric acid-to-Cre ratio and neonatal PLR was detected (r: 0.193; p: 0.013). Moreover, moderate negative correlations between maternal PLR (r:-0.231, p: 0.002), uric acid (r: 0.332, p:0.000) and adverse neonatal outcomes were found. Uric acid and PLR, which can be easily calculated clinically may predict adverse neonatal outcomes.IMPACT STATEMENTWhat is already known about this topic? Preeclampsia is known as a significant cause of maternal morbidity and mortality. Haematological indices have been evaluated for the prognosis of many kinds of disease.What do the results of this study add? This study has focussed on new combined haematological-biochemical indices and its relationship with neonatal outcomes. Both higher NLR, derived NLR, DNI and lower PLR were recorded as useful markers for preeclampsia.What are the implications of these findings for clinical practice and/or further research? Some indices that were calculated by assessing basic and simple blood parameters may help clinicians to predict clinical outcomes of 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.

Assessing the Role of Uric Acid as a Predictor of Preeclampsia

We assessed the diagnostic utility of uric acid for the prediction of preeclampsia. An observational prospective approach was carried out during 2014. Preeclamptic women were classified into 4 groups accordingly to the onset of preeclampsia and the presence of intrauterine growth restriction (IUGR). Serum uric acid levels, urea, and creatinine were measured. Receiver operating curves (ROC) of the uric acid levels ratio (UAr) between a dosage before and after the 20th week of gestation were performed. One thousand two hundred and ninety-third pregnant women were enrolled in this study. Eight hundred ten had non-complicated pregnancies, 40 preeclampsia, 33 gestational hypertension, and 20 IUGR without preeclampsia. Uric acid significantly raised after 20 weeks of gestation in women who develop preeclampsia before 34 weeks (Group A) or in those who develop preeclampsia after 37 weeks associated with IUGR (Group C). In women who develop preeclampsia after 34 weeks without IUGR (Groups B and D), uric acid increased after the 30th week of gestation. In all groups, UAr was greater than 1.5. In gestational hypertension, UAr was superior to 1.5 toward the end of gestation, while in IUGR without preeclampsia, the behavior of serum uric acid was similar to non-complicated pregnancies. In all cases, urea and creatinine showed normal values, confirming that patients had no renal compromise. ROC area was 0.918 [95% confidence interval (CI): 0.858–0.979) for the preeclampsia group and 0.955 (95% CI: 0.908–1.000) for Group A. UAr at a cut-off point ≥1.5 had a very low positive predictive value, but a high negative predictive value of 99.5% for preeclampsia and it reached 100% for Group A. Thus, a UAr less than 1.5 may be a helpful parameter with a strong exclusion value and high sensitivity for those women who are not expected to develop preeclampsia. Additionally, this low-cost test would allow for better use of resources in developing countries.

Characterizing and Evaluating Diurnal Salivary Uric Acid Across Pregnancy Among Healthy Women

Uric acid levels during pregnancy have been examined as a potential indicator of risk for gestational diabetes mellites, hypertension, and related adverse birth outcomes. However, evidence supporting the utility of serum uric acid levels in predicting poor maternal and fetal health has been mixed. The lack of consistent findings may be due to limitations inherent in serum-based biomeasure evaluations, such as minimal repeated assessments and variability in the timing of these assessments. To address these gaps, we examined repeated measurements of diurnal salivary uric acid (sUA) levels in a sample of 44 healthy women across early-mid and late pregnancy. We assessed potential covariates and confounds of sUA levels and diurnal trajectories, as well as associations between maternal weight gain and blood pressure during pregnancy and sUA concentrations. Using multilevel linear models, we found sUA increased across pregnancy and displayed a robust diurnal pattern with the highest concentrations at waking, a steep decline in the early morning, and decreasing levels across the day. Maternal pre-pregnancy BMI, age, prior-night sleep duration, and fetal sex were associated with sUA levels and/or diurnal slopes. Maternal blood pressure and gestational weight gain also showed significant associations with sUA levels across pregnancy. Our results expand upon those found with serum UA measurements. Further, they demonstrate the feasibility of using at-home, minimally-invasive saliva sampling procedures to track UA levels across pregnancy with potential applications for the long-term monitoring of maternal cardiometabolic risk.

Towards the Use of Adsorption Methods for the Removal of Purines from Beer

Beer corresponds to a fermented alcoholic beverage composed of several components, including purine compounds. These molecules, when ingested by humans, can be catabolized into uric acid, contributing to uric acid’s level increase in serum, which may lead to hyperuricemia and gout. To assure a proper management of this disease, physicians recommend restrictive dietary measures, particularly by avoiding the consumption of beer. Therefore, it is of relevance to develop efficient methods to remove purine compounds from alcoholic beverages such as beer. In this review, we provide an introduction on fermented alcoholic beverages, with emphasis on beer, as well as its purine compounds and their role in uric acid metabolism in the human body in relation to hyperuricemia and gout development. The several reported enzymatic, biological and adsorption methods envisaging purine compounds’ removal are then reviewed. Some enzymatic and biological methods present drawbacks, which can be overcome by adsorption methods. Within adsorption methods, adsorbent materials, such as activated carbon or charcoal, have been reported and applied to beer or wort samples, showing an excellent capacity for adsorbing and removing purine compounds. Although the main topic of this review is on the removal of purine compounds from beer, other studies involving other matrices rather than beer or wort that are rich in purines are included, since they provide relevant clues on designing efficient removal processes. By ensuring the selective removal of purine compounds from this beverage, beer can be taken by hyperuricemic and gouty patients, avoiding restrictive dietary measures, while decreasing the related healthcare economic burden.

Angiogenic markers and their longitudinal change for predicting adverse outcomes in pregnant women with chronic hypertension

BACKGROUND

Women with chronic hypertension are at increased risk for adverse maternal and perinatal outcomes. Maternal serum angiogenic markers, such as soluble fms-like tyrosine kinase 1 and placental growth factor, can be used to triage women with suspected preeclampsia. However, data about these markers in pregnant women with chronic hypertension are scarce.

OBJECTIVE

We aimed to evaluate the predictive accuracy of maternal serum levels of soluble fms-like tyrosine kinase 1, placental growth factor, and their ratio for predicting adverse maternal and perinatal outcomes in women with chronic hypertension.

STUDY DESIGN

This was a retrospective analysis of prospectively collected data from January 2013 to October 2019 at the University of Vienna Hospital, Vienna, Austria. The inclusion criteria were pregnant women with chronic hypertension and suspected preeclampsia. The primary outcome of this study was the prognostic performance of angiogenic markers for the prediction of adverse maternal and perinatal outcomes in pregnant women with chronic hypertension. The accuracy of angiogenic markers for predicting adverse composite outcomes was assessed with a binomial logistic regression. The accuracy of each marker was assessed using receiver operating characteristics curves and area under the curve values. Area under the curve values were compared using De Long's test.

RESULTS

Of the 145 included women with chronic hypertension and suspected superimposed preeclampsia, 26 (17.9%) women developed complications (ie, composite adverse maternal or fetal outcomes) within 1 week of assessment (average gestational age at assessment, 29.9 weeks) and 35 (24.1%) developed complications at any time (average gestational age at assessment, 30.1 weeks). In women who developed complications at any time, the median maternal serum soluble fms-like tyrosine kinase-1 to placental growth factor ratio was 149.4 (interquartile range, 64.6-457.4) compared with 8.0 (interquartile range, 3.37-41.2) for women who did not develop complications (P<.001). The area under the curve values for the maternal serum soluble fms-like tyrosine kinase-1 to placental growth factor ratio Z-score (0.95; 95% confidence interval, 0.90-0.99) and placental growth factor level Z-score (0.94; 95% confidence interval, 0.88-0.99) for predicting complications within 1 week of assessment were very high. The area under the curve values for new-onset edema (0.61; 95% confidence interval, 0.52-0.70), proteinuria (0.62; 95% confidence interval, 0.52-0.71), high mean arterial pressure (0.52; 95% confidence interval, 0.50-0.54), and other symptoms of preeclampsia (0.57; 95% confidence interval, 0.49-0.65) were all significantly lower than for the angiogenic markers (P<.001 for all). Women who had an angiogenic imbalance and/or proteinuria had the highest rate of complications (28/57, 49.1%). The rate of complications in women with an angiogenic imbalance and/or proteinuria was significantly higher than in women with either proteinuria, other symptoms, or intrauterine growth restriction in the absence of an angiogenic imbalance (49.1% vs 16.7%; P=.039). The highest positive and negative predictive values for predicting adverse outcomes were demonstrated by an angiogenic imbalance and/or proteinuria criteria with a positive predictive value of 49.1% (95% confidence interval, 50.4%-57.9%) and a negative predictive value of 92% (95% confidence interval, 85.5%-95.8%). Longitudinal changes in measurements of the gestational age-corrected ratio of soluble fms-like tyrosine kinase-1 to placental growth factor up to the last measurement had a significantly higher area under the curve value than the last measurement alone (area under the curve, 0.95; 95% confidence interval, 0.92-0.99 vs 0.87; 95% confidence interval, 0.79-0.95; P=.024) CONCLUSION: Maternal serum angiogenic markers are superior to clinical assessment in predicting adverse maternal and perinatal outcomes in pregnant women with chronic hypertension. Repeated measurements of the ratio of soluble fms-like tyrosine kinase-1 to placental growth factor seems beneficial given the better predictive accuracy compared with a single measurement alone. The use of angiogenic makers should be implemented in clinical management guidelines for pregnant women with chronic hypertension.

Maternal serum uric acid: a reliable prognostic indicator of foetal outcome among pre-eclamptic patients in a low resource setting

BACKGROUND

Pre-eclampsia is a major cause of maternal and fetal morbidity and mortality in both developed and developing countries. Hyperuricemia is often associated with pre-eclampsia and when this occurs, fetal outcome may become worse. We evaluated the role of maternal serum uric acid as a prognostic indicator of fetal outcome in pre-eclamptic mothers.

METHODS

A prospective case-control study in which 55 eligible pre-eclamptic patients at term were matched in maternal age and gestational age with 55 consecutive normotensive pregnant women. Venous blood samples were obtained and analyzed for serum uric acid. Following delivery, the fetal outcomes in the pre-eclamptic group and controls were determined. Data analysis was carried out using SPSS (version 21) and the level of statistical significance was set at p-value <.05.

RESULTS

The mean serum uric acid levels of the pre-eclamptic subjects was significantly higher compared to their normotensive counterparts (12.7 ± 7.8 vs. 4.9 ± 1.2 mg/dL, p = .000). Babies with low birth weight, poor Apgar scores (at 1st and 5th minute of life) and those who required neonatal unit admission occurred more significantly among the pre-eclamptic women when compared with the controls (p = .000). However, the live birth rate of the case and control groups was comparable (94.5% vs. 100%, p = .079), Binary logistic regression analysis revealed a positive association between hyperuricemia and pre-eclampsia (OR = 18.8; 95% CI = 1.22-289.35, p = .035). Pre-eclamptic mothers with hyperuricemia had 4.41 odds of delivering babies with low birth weight when compared with pre-eclamptics without hyperuricemia (OR = 4.41; 95% CI = 0.76-25.5, p = .097); but Apgar scores and need for neonatal admission showed no association with maternal serum uric acid levels.

CONCLUSION

This study therefore suggests that hyperuricemia is a strong prognostic indicator of LBW babies among women with pre-eclampsia.

Association between Serum Uric Acid Levels and Perinatal Outcome in Women with Preeclampsia

Objectives

To compare serum uric acid levels with disease severity and perinatal outcome among preeclamptic and normal pregnant women.

Materials and Methods

This was a case-control study carried out in Federal Medical Centre, Umuahia, Nigeria. Consenting pregnant women were consecutively recruited into two groups comprising pregnant women diagnosed with preeclampsia and normotensive nonproteinuric pregnant women. Exclusion criteria included pregnant women who were current smokers, took alcohol, and diagnosed with multiple gestation, diabetes mellitus, or renal failure. Associations between categorical variables such as preeclampsia severity and perinatal outcomes were done using logistic regression while means of continuous variables such as serum uric acid were compared using Student's t-test. Data were presented using odds ratios (ORs) with 95% confidence intervals (95% CI) and a statistical significance level set at P value ˂ 0.05. Data analysis was done using Statistical Package for Social Sciences version 22.

Results

One hundred and two participants were finally analysed. Fifty-one participants were recruited in each arm. Women with preeclampsia had significantly high serum uric acid level versus controls (6.08 ± 0.49 mg/dL vs. 5.20 ± 0.19; P < 0.001). Women with elevated serum uric acid levels (˃6 mg/dL) were found to be 4 times more likely to have severe preeclampsia (P=0.022, OR = 4.00, 95% CI = 1.225–13.056), 66 times more likely to have APGAR score ˂7 in the first minute (P < 0.001, OR = 66.00, 95% CI = 6.991–623.128), and 3 times more likely to have lower birth weight (P=0.038, OR = 3.400, 95% CI = 1.073–10.775) than those with normal serum uric acid levels.

Conclusions

The mean serum uric acid level in a preeclamptic is higher than that of normal pregnant control, and higher levels are associated with severity of the disease and significantly associated with poorer perinatal outcome.

Shedding light on the pathophysiology of preeclampsia-syndrome in the era of Cardio-Obstetrics: Role of inflammation and endothelial dysfunction

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Preeclampsia (PE) is a worldwide pregnancy complication with serious maternal and neonatal consequences. Our understanding of PE pathophysiology has significantly evolved over the last decades by recognizing that endothelial dysfunction and systemic inflammation, with an associated angiogenic imbalance, are key pieces of this still incomplete puzzle. In the present era, where no single treatment to cure or treat this obstetric condition has been developed so far, PE prevention and early prediction poses the most useful clinical approach to reduce the PE burden. Although most PE episodes occur in healthy nulliparous women, the identification of specific clinical conditions that increase dramatically the risk of PE provides a critical opportunity to improve outcomes by acting on potential reversible factors, and also contribute to better understand this pathophysiologic enigma. In this review, we highlight major clinical contributors of PE and shed light about their potential link with endothelial dysfunction and inflammation.

Angiogenic markers predict kidney injury and obstetric complications in women with preeclampsia and pregnancy-related acute kidney injury

Pregnancy-related acute kidney injury (PRAKI) particularly on top of preeclampsia (PE) represents a major cause of maternal and fetal morbidity and mortality. Reliable diagnostic tools are needed to further evaluate the diagnosis and prognosis of PRAKI. Our objective was to study the diagnostic and prognostic value of angiogenic markers (e.g., stromal cell-derived factor 1 (SDF-1), vascular endothelial growth factor (VEGF), alarmins as uric acid) in women with PE and PRAKI. This prospective study included three groups; PRAKI, PE patients, and healthy controls that were compared regarding serum levels of the studied markers correlated to renal, maternal, and fetal outcomes. SDF-1, VEGF, and uric acid levels were significantly different between the three included groups and predicted PRAKI diagnosis. Patients with hemolysis, elevated liver enzymes, and low platelet (HELLP) syndrome exhibited the highest titers of SDF-1 and VEGF. A positive correlation was found between SDF-1 and renal recovery. Conclusively, serum assays of SDF-1, VEGF, and uric acid may add a diagnostic value in PRAKI and PE.

Foetal and maternal outcomes in hyperuricaemia pre-eclampsia patients in Hospital Universiti Sains Malaysia

Preeclampsia patients have frequently been found to experience hyperuricaemia and this may result in poor outcomes compared to those with normal uric acid levels. This study aimed to determine the relationship of hyperuricaemia in pre-eclampsia patients with foetal and maternal outcomes. This prospective cohort study involved 79 patients in a tertiary centre from year 2016 to 2018. Blood samples were taken antenatally and at the 6th week, post-delivery for renal function including serum uric acid level. Our findings indicate that there was a higher incidence of poor maternal and foetal outcomes in the hyperuricaemia group than the normal uric acid group. Serum uric acid has been shown to be a significant predictor for low birth weight and premature delivery in preeclampsia patients. It was also found that there was a significant negative correlation between uric acid level and antenatal creatinine clearance (r_s = -0.338, p = .002). The assessment of the serum uric acid level seems to be important to ensure better outcomes in patients with preeclampsia.Impact statementWhat is already known on this subject? Preeclampsia is a serious pregnancy-related complication and remains as one of the most important cause of maternal and foetal morbidity and mortality, affecting 2-8% in all pregnancy. Many studies have established the association between hyperuricaemia and preeclampsia. Besides, numerous studies have found that hyperuricaemia contributed to adverse maternal and foetal outcomes.What the results of this study add? There was a significant increase in adverse foetal and maternal outcomes in the hyperuricaemia group compared to the normal uric acid group. This study revealed that serum uric acid remains a significant predictor for low birth weight and premature delivery in preeclampsia patients.What the implications are of these findings for clinical practice and/or further research? Hyperuricaemia does not merely become an indicator for the severity of disease in preeclampsia patients but also indicates adverse foetal outcomes. Large population-based studies are required to establish the absolute maternal and foetal outcomes in patients with hyperuricaemia. Besides, further studies are recommended on long-term implication of hyperuricaemia which is not limited to only during antenatal period.

Prediction of stillbirth: an umbrella review of evaluation of prognostic variables

BACKGROUND

Stillbirth accounts for over 2 million deaths a year worldwide and rates remains stubbornly high. Multivariable prediction models may be key to individualised monitoring, intervention or early birth in pregnancy to prevent stillbirth.

OBJECTIVES

To collate and evaluate systematic reviews of factors associated with stillbirth in order to identify variables relevant to prediction model development.

SEARCH STRATEGY

MEDLINE, Embase, DARE and Cochrane Library databases and reference lists were searched up to November 2019.

SELECTION CRITERIA

We included systematic reviews of association of individual variables with stillbirth without language restriction.

DATA COLLECTION AND ANALYSIS

Abstract screening and data extraction were conducted in duplicate. Methodological quality was assessed using AMSTAR and QUIPS criteria. The evidence supporting association with each variable was graded.

RESULTS

The search identified 1198 citations. Sixty-nine systematic reviews reporting 64 variables were included. The most frequently reported were maternal age (n = 5), body mass index (n = 6) and maternal diabetes (n = 5). Uterine artery Doppler appeared to have the best performance of any single test for stillbirth. The strongest evidence of association was for nulliparity and pre-existing hypertension.

CONCLUSION

We have identified variables relevant to the development of prediction models for stillbirth. Age, parity and prior adverse pregnancy outcomes had a more convincing association than the best performing tests, which were PAPP-A, PlGF and UtAD. The evidence was limited by high heterogeneity and lack of data on intervention bias.

TWEETABLE ABSTRACT

Review shows key predictors for use in developing models predicting stillbirth include age, prior pregnancy outcome and PAPP-A, PLGF and Uterine artery Doppler.

Evaluation of obstructive sleep apnea prevalence in mothers of infants with low birth weight and its relationship with serum uric acid levels as a hypoxia marker

OBJECTIVE

Serum uric acid level, which is an oxidative stress marker, may increase in some conditions that lay the ground for the hypoxia. However, recent literature lacks studies with large series on this subject. We aimed to examine the incidence of OSAS in mothers who delivered a low birth weight baby and its association with serum uric acid levels as a hypoxia marker.

METHODS

We enrolled 143 pregnant women, 44 of whom delivered a low birth weight (LBW) baby. We made a face-to-face interview in which we asked the questions in the patient follow-up form, comprising three sections. The form included questions regarding the sociodemographic features and obstetric history of the participant women, besides the Berlin Questionnaire and the Epworth Sleepiness Scale. We recorded the blood test parameters that are obtained from patient records in the last section.

RESULTS

Mean uric acid (UA) levels of mothers with a LBW baby (n = 44, birth weight below 2500 g) were 4.51 ± 1.23 mg/dL (min-max = 2.7-8.0) while the UA levels in mothers of normal weighted (NBW) babies (n = 99, birth weight is 2500 g or above) were 4.08 ± 0.75 (min-max = 2.6-6.1 mg/dL). The UA levels of mothers who delivered LBW infants were significantly higher compared with the mothers of NBW babies (p = .010).

CONCLUSION

Uric acid levels can be used as a prognostic parameter for the closer monitoring of pregnant women who have been diagnosed with small-for-gestational-age babies during pregnancy.

Hyperuricaemia and gout in cardiovascular, metabolic and kidney disease

During the last century, there has been an increasing prevalence of hyperuricaemia noted in many populations. While uric acid is usually discussed in the context of gout, hyperuricaemia is also associated with hypertension, chronic kidney disease, hypertriglyceridaemia, obesity, atherosclerotic heart disease, metabolic syndrome, and type 2 diabetes. Here we review the connection between hyperuricaemia and cardiovascular, kidney and metabolic diseases. Contrary to the popular view that uric acid is an inert metabolite of purine metabolism, recent studies suggest serum uric acid may have a variety of pro-inflammatory, pro-oxidative and vasoconstrictive actions that may contribute to cardiometabolic diseases. Hyperuricaemia is a predictive factor for the development of hypertension, metabolic syndrome, type 2 diabetes, coronary artery disease, left ventricular hypertrophy, atrial fibrillation, myocardial infarction, stroke, heart failure and chronic kidney disease. Treatment with uric acid-lowering therapies has also been found to improve outcomes in patients with hypertension and kidney disease, in some but not all studies. In conclusion, uric acid is emerging as a potentially treatable risk factor for cardiometabolic diseases, and more clinical trials investigating the potential benefit of lowering serum uric acid are recommended in individuals with hyperuricaemia with and without deposition and concomitant hypertension, metabolic syndrome or chronic kidney disease.

Predictive value of serum uric acid levels for adverse maternal and perinatal outcomes in pregnant women with high blood pressure. A systematic review and meta-analysis

OBJECTIVE

High serum uric acid seems to be associated with pre-eclampsia. The expected utility of uric acid is related to the probability of occurrence of maternal and neonatal complications. We evaluated the accuracy of uric acid in predicting adverse maternal and perinatal outcomes in pregnant women with high blood pressure.

METHODS

We performed an electronic search for studies evaluating the accuracy of high serum uric acid levels in pregnant women with high blood pressure. The assessment of risk of bias was performed using the QUIPS tool. For each included study, we collected data about study characteristics and diagnostic test accuracy to construct 2 × 2 tables. Pooled sensitivity (Se), specificity (Sp) and diagnostic odds ratio (DOR) were estimated using a bivariate model. Grading the quality of the evidence was assessed using the GRADE approach.

RESULTS

Twenty-one studies, testing more than 6,000 women, met the inclusion criteria. The majority of studies were at low risk of bias. Ten studies evaluated the role of serum uric acid to predict pre-eclampsia, the pooled Se was 0.74 (95%CI 0.71-0.77), Sp was 0.66 (95%CI 0.63-0.68), and DOR was 9.67 (95%CI 4.57-20.47). The overall quality of evidence was evaluated as low. The GRADE rating was downgraduate for risk of bias and inconsistency.

CONCLUSIONS

No robust evidence currently exists to suggest that uric acid measurement is useful in predicting maternal and perinatal adverse outcomes.

Salivary uric acid as a predictive test of preeclampsia, pregnancy-induced hypertension and preterm delivery: A pilot study

INTRODUCTION

There remains a need for a non-invasive, low-cost and easily accessible way of identifying women at risk of developing hypertensive disorders in pregnancy. This study evaluated the predictive value of longitudinal salivary uric acid measurement.

MATERIAL AND METHODS

Pregnant women (n = 137) from 20 weeks of gestation were recruited at St Richards Hospital, Chichester, UK, for this prospective cohort study. Weekly samples of salivary uric acid were analyzed until delivery. Information regarding pregnancy and labor were obtained from the patient's record after delivery. Independent t tests were used to compare mean levels of salivary uric acid in women with hypertensive complications and adverse fetal outcomes with women with normal pregnancies. Main outcome measures were preeclampsia, pregnancy-induced hypertension, spontaneous preterm delivery and small-for-gestational-age babies.

RESULTS

From 21 weeks of gestation until delivery, levels of salivary uric acid increased significantly in women who subsequently developed preeclampsia and pregnancy-induced hypertension compared with women with normal pregnancies (preeclampsia-mean at gestational age 21-24, 95% confidence interval [95% CI] [mean _GA21-24 ): 108 [63-185] vs 47 (39-55) µmol/L; P = .005; pregnancy-induced hypertension-mean _GA21-24 : 118 [54-258] vs 47 [39-55] µmol/L; P = .004). In women who had spontaneous preterm delivery, salivary uric acid levels increased significantly from 29 to 32 weeks of gestation compared with women with normal pregnancies (mean _GA29-32 : 112 (57-221) vs 59 (50-71) µmol/L; P = .04). In women who had babies small-for-gestational-age <10th percentile and small-for-gestational-age <3rd percentile, differences in salivary uric acid levels were insignificant.

CONCLUSIONS

Elevated levels of salivary uric acid precede the onset of preeclampsia, pregnancy-induced hypertension and preterm delivery. Salivary uric acid may prove to be an early biomarker of hypertensive complications of pregnancy and spontaneous preterm delivery.

The Prognostic Value of Angiogenic Markers in Twin Pregnancies to Predict Delivery Due to Maternal Complications of Preeclampsia

The sFlt-1 (soluble fms-like tyrosine kinase-1), PlGF (placental growth factor), and their ratio are useful for predicting delivery because of preeclampsia in singleton pregnancies. Evidence on the utility of sFlt-1/PlGF ratio in twin pregnancies is lacking. We aimed to evaluate the predictive value of sFlt-1/PlGF ratio for delivery because of preeclampsia in twins. A retrospective data analysis of 164 twin pregnancies with suspected preeclampsia was performed. The sFlt-1/PlGF ratio, which was known to clinicians, was significantly higher in women who delivered within 1 and 2 weeks compared with those who did not (median: 98.9 and 84.2 versus 23.5 pg/mL, respectively; P<0.001). The area under the curve values sFlt-1/PlGF ratio levels were 0.88 (95% CI, 0.83-0.84) and 0.88 (95% CI, 0.83-0.93) for predicting delivery because of preeclampsia within 1 and 2 weeks of blood sampling, respectively. The predictive accuracy of sFlt-1/PlGF was independent of gestational age at sampling and chorionicity (P>0.100 for interaction). The area under the curve values of sFlt-1/PlGF were significantly higher than for PlGF alone (mean 0.88 and 0.88 versus 0.81 and 0.80) for predicting delivery because of preeclampsia within 1 and 2 weeks of blood sampling (P=0.055 and 0.001, respectively). sFlt-1/PlGF ratio lower than 38 was able to rule-out delivery within 1 and 2 weeks with a negative predictive value of 98.8% and 96.4% for delivery because of preeclampsia within 1 and 2 weeks, respectively. A cutoff of 38 is applicable for ruling out delivery because of preeclampsia in twin pregnancies.

Implementation of a Clinical Decision Laboratory Ordering Algorithm for Preeclampsia: A Quality Improvement Initiative

OBJECTIVE

Pregnant women with suspected or diagnosed preeclampsia receive laboratory investigations. Our institutional protocols were outdated and not evidence based. However, guidelines lack clear direction to support cost-effective use. We aimed to reduce unnecessary laboratory tests, while supporting physicians with investigation selection.

METHODS

A quality improvement (QI) approach was used to analyze the ordering process in the obstetrics wards of a tertiary care centre. Health care providers were surveyed on their laboratory ordering practices, and their responses corroborated with chart reviews. An algorithm for ordering preeclampsia investigations was developed by a multidisciplinary team, implemented, and posted on the wards. Pocket aides were also distributed, and the algorithm tool was supported by educational seminars. Laboratory usage volume and costs were analyzed pre- and post-intervention. Post-intervention impact surveys, informal interviews, and chart reviews were performed in plan-do-study-act (PDSA) cycles.

RESULTS

Most health care providers ordered broad panels of investigations and re-evaluated patients at inconsistent intervals. Almost none were aware of the laboratory costs associated with this testing. Most respondents acknowledged that some of the investigations they ordered did not affect patient care. Baseline data (Sept 2016-Aug 2017) showed 2923 tests ordered monthly (CAD$18 306). Post-intervention data (Sept 2017-Aug 2019) revealed a 39.9% reduction in costs related to blood tests (a savings of CAD$7304/mo), particularly those tests of lower clinical utility. The performance of essential investigations, such as measurement of creatinine levels, were similar pre- and post-intervention, and thus acted a control measure. The effects of this intervention were sustained.

CONCLUSIONS

This simple and inexpensive intervention reduced unnecessary ordering of preeclampsia investigations. This resulted in annualized savings of CAD$87 643 and reduced iatrogenic blood loss, with no evidence of harm. Efforts to scale and spread this clinical tool will further improve health care delivery for pregnant patients.

Gene polymorphisms of uric acid are associated with pre-eclampsia in South Africans of African ancestry

Objectives: To investigate the association of uric acid gene polymorphisms and Pre-eclampsia.Methods: 637 women of African ancestry [280 controls, 357 pre-eclampsia (early-onset = 187, late-onset = 170]) retrospectively. The rs505802, rs1212986, and rs1014290 SNPs were genotyped from purified DNA using real-time PCR.Results: CT genotype (rs505802) was higher in pre-eclampsia [Adjusted p = 0.028*: OR (95% CI) = 1.73 (1.258-2.442)] and late-onset pre-eclampsia [Adjusted p = 0.027*: OR (95% CI) = 1.75 (1.165-2.2628)] than controls. CT genotype (rs1014290) was higher in early-onset pre-eclampsia [Adjusted p-value = 0.040*: OR (95% CI) = 1.60 (1.102-2.325)] than controls.Conclusion: The genotyped rs505802 and rs1014290 are significantly associated with pre-eclampsia.

Reappraisal of the relationship between 24-hour proteinuria and preeclampsia in terms of the maternal and perinatal outcomes

Objective: This study evaluated the association between proteinuria levels and maternal, and perinatal outcomes of preeclampsia patients and determined the cutoff values for predicting severe complications.Methods: We retrospectively evaluated the records of 412 patients with proteinuric preeclampsia.Results: Median proteinuria levels were significantly higher in patients with severe maternal and adverse perinatal outcomes than in those without such outcomes, except in cases of placental abruption and late preterm delivery.Conclusion: Proteinuria levels may aid in diagnosing preeclampsia and indicating early intervention. The revised guidelines do not suggest that proteinuria encountered during pregnancy is clinically insignificant.

Preeclampsia: Risk Factors, Diagnosis, Management, and the Cardiovascular Impact on the Offspring

Hypertensive disorders of pregnancy affect up to 10% of pregnancies worldwide, which includes the 3%–5% of all pregnancies complicated by preeclampsia. Preeclampsia is defined as new onset hypertension after 20 weeks’ gestation with evidence of maternal organ or uteroplacental dysfunction or proteinuria. Despite its prevalence, the risk factors that have been identified lack accuracy in predicting its onset and preventative therapies only moderately reduce a woman’s risk of preeclampsia. Preeclampsia is a major cause of maternal morbidity and is associated with adverse foetal outcomes including intra-uterine growth restriction, preterm birth, placental abruption, foetal distress, and foetal death in utero. At present, national guidelines for foetal surveillance in preeclamptic pregnancies are inconsistent, due to a lack of evidence detailing the most appropriate assessment modalities as well as the timing and frequency at which assessments should be conducted. Current management of the foetus in preeclampsia involves timely delivery and prevention of adverse effects of prematurity with antenatal corticosteroids and/or magnesium sulphate depending on gestation. Alongside the risks to the foetus during pregnancy, there is also growing evidence that preeclampsia has long-term adverse effects on the offspring. In particular, preeclampsia has been associated with cardiovascular sequelae in the offspring including hypertension and altered vascular function.

Uric acid levels in gestational hypertensive women predict preeclampsia and outcome of small-for-gestational-age infants

OBJECTIVE

This study aims to ascertain whether serum uric acid is a suitable predictor of preeclampsia and/or the delivery of small-for-gestational-age infants for women with gestational hypertension.

METHODS

364 singleton pregnant women with initial presentation of gestational hypertension were recruited and followed up until 6 weeks after delivery. Uric acid z score and binary logistic regression analysis were applied to establish the relationship between serum uric acid and the chance of progression to preeclampsia and giving birth to a small-for-gestational-age infant. Furthermore, receiver operating characteristic (ROC) analysis was used to evaluate the prediction value of serum uric acid.

RESULTS

Uric acid z score and binary logistic regression analysis indicated that elevated serum uric acid increased the chances of gestational hypertension progression to preeclampsia and subsequent delivery of small-for-gestational-age infants. ROC analysis showed that serum uric acid at a cutoff value of 303μmol l-1, moderately predict the development of preeclampsia and the delivery of small-for-gestational age infants. The prediction values of preeclampsia were 90.7% sensitivity, 69.4% specificity, 97.7% negative predictor values and 34.0% positive predictor values, comparatively, the prediction value for small-for-gestational age infant was low. The ROC curve improved with 95.8% sensitivity, 86.7% specificity, 98.1% NPV, and 74.2% PPV in the Chinese Han women with early onset of gestational hypertension thus the diagnosis of gestational hypertension before 34 weeks.

CONCLUSIONS

Elevated serum uric acid in Chinese Han women with gestational hypertension indicated an increased risk of their progression to preeclampsia and the further delivering of small-for-gestational-age infants.

Predictive value of serum uric acid levels for adverse perinatal outcomes in preeclampsia

Preeclampsia is a multisystem disorder associated with pregnancy and is a common cause of perinatal morbidity. The aim of this study was to determine whether elevated serum uric acid levels, alone or in combination with other laboratory factors could predict preeclampsia in women with adverse perinatal outcomes.We conducted a prospective observational study of women who were admitted to Soonchunhyang University Cheonan Hospital from January 2016 to December 2016. Demographic, clinical and laboratory data were collected for each pregnancy at the time of delivery. Women were grouped according to status (preeclampsia or normotensive), and a logistic regression analysis was used to determine the relationship between serum uric acid levels and adverse outcomes.The mean age of the study participants was 31.3 ± 5.0 years. In patients with preeclampsia, serum uric acid level was associated with the severity of preeclampsia, including blood pressure (R = 0.321, P = .014), serum creatinine levels (R = 0.505, P < .001), and proteinuria (P = .014), as well as adverse fetal outcomes, including preterm labor (P = .027) and low birth weight delivery (P = .001). The optimal maternal serum uric acid threshold that predicted low birth weight at delivery was 6.35 mg/dL (sensitivity, 0.58; specificity, 0.95). The multivariable logistic regression model that was used to predict low birth weight at delivery displayed an area under the receiver-operating characteristic curve of 0.902 (95% confidence interval, 0.817-0.986).In women with preeclampsia, maternal serum uric acid level is an important parameter for predicting low birth weight. Additionally, the combination of uric acid, hemoglobin, and bilirubin levels appear to be optimal for predicting low birth weight in women with preeclampsia.

Hypertensive Disorders of Pregnancy

The 4 categories of hypertensive disorders of pregnancy are chronic hypertension, gestational hypertension, preeclampsia-eclampsia, and chronic hypertension with superimposed preeclampsia. These disorders are among the leading causes of maternal and fetal morbidity and mortality. Proper diagnosis in the emergency department is crucial in order to initiate appropriate treatment to reduce the potential harm to the mother and the fetus. Prompt management should be undertaken when the blood pressure is greater than 160/110 mm Hg or there are other severe features such as acute kidney injury, elevated liver function tests, severe abdominal pain, pulmonary edema, and central nervous system disturbances.

Uric Acid and Xanthine Levels in Pregnancy Complicated by Gestational Diabetes Mellitus-The Effect on Adverse Pregnancy Outcomes

Uric acid (UA) levels are associated with many diseases including those related to lifestyle. The aim of this study was to evaluate the influence of clinical and anthropometric parameters on UA and xanthine (X) levels during pregnancy and postpartum in women with physiological pregnancy and pregnancy complicated by gestational diabetes mellitus (GDM), and to evaluate their impact on adverse perinatal outcomes. A total of 143 participants were included. Analyte levels were determined by HPLC with ultraviolet detection (HPLC-UV). Several single-nucleotide polymorphisms (SNPs) in UA transporters were genotyped using commercial assays. UA levels were higher within GDM women with pre-gestational obesity, those in high-risk groups, and those who required insulin during pregnancy. X levels were higher in the GDM group during pregnancy and also postpartum. Positive correlations between UA and X levels with body mass index (BMI) and glycemia levels were found. Gestational age at delivery was negatively correlated with UA and X levels postpartum. Postpartum X levels were significantly higher in women who underwent caesarean sections. Our data support a possible link between increased UA levels and a high-risk GDM subtype. UA levels were higher among women whose glucose tolerance was severely disturbed. Mid-gestational UA and X levels were not linked to adverse perinatal outcomes.

Evaluation of serum biomarkers for detection of preeclampsia severity in pregnant women

Objectives

To determine serum biomarkers in detection of preeclampsia severity among pregnant women.

Methods

Among 450 pregnant women with various severity of preeclampsia, serum biomarkers ofaspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), hemoglobin (Hb), platelet count (PLT), uric acid, direct bilirubin, total bilirubin, creatinine, and alkaline phosphatase were compared using area under the Receiver operating characteristic (ROC) curve and Area Under the Curve (AUC).

Results

The mean age of women was 30.63±6.43 years and with mean gestational age of 34.69±3.97 weeks. The mean level of LDH, ALT, uric acid, and creatinine were significantly higher in the women with severe type of preeclampsia compared to those with mild type. LDH level had ROC and AUC of more than 0.80, with highest sensitivity, and moderatespecificityin comparison to other markers.

Conclusion

Biomarkers such as ALT, uric acid, and LDH were shown to be prognostic in detection of theseverity of preeclampsia. LDH was demonstrated to significantly be a better prognostic test in detection of preeclampsia severity.

The Role of Uric Acid in Preeclampsia: Is Uric Acid a Causative Factor or a Sign of Preeclampsia?

PURPOSE OF REVIEW

Because of the significant discrepancies on this topic, this review will focus on the role of uric acid in PE, uric acid as a predictor of preeclampsia and fetal growth retardation. We considered eligible review and original articles relevant to the research question.

RECENT FINDINGS

Hypertensive disorders of pregnancy such as preeclampsia (PE) are a major cause of both maternal and fetal morbidity and mortality worldwide. Uric acid has been reported as a key factor contributing to the pathogenesis of PE. Some studies have indicated that serum uric acid levels increase with the severity of PE, while several studies have shown contradictory results. Some studies suggested high uric acid levels lead to PE, while others state that PE causes an increase in uric acid levels. Despite the strong association of uric acid in the pathogenesis of preeclampsia, current data is still contradictory hence genetic and high-end laboratory investigations may clarify this enigma.

Development and validation of Prediction models for Risks of complications in Early-onset Pre-eclampsia (PREP): a prospective cohort study

BACKGROUND

The prognosis of early-onset pre-eclampsia (before 34 weeks' gestation) is variable. Accurate prediction of complications is required to plan appropriate management in high-risk women.

OBJECTIVE

To develop and validate prediction models for outcomes in early-onset pre-eclampsia.

DESIGN

Prospective cohort for model development, with validation in two external data sets.

SETTING

Model development: 53 obstetric units in the UK. Model transportability: PIERS (Pre-eclampsia Integrated Estimate of RiSk for mothers) and PETRA (Pre-Eclampsia TRial Amsterdam) studies.

PARTICIPANTS

Pregnant women with early-onset pre-eclampsia.

SAMPLE SIZE

Nine hundred and forty-six women in the model development data set and 850 women (634 in PIERS, 216 in PETRA) in the transportability (external validation) data sets.

PREDICTORS

The predictors were identified from systematic reviews of tests to predict complications in pre-eclampsia and were prioritised by Delphi survey.

MAIN OUTCOME MEASURES

The primary outcome was the composite of adverse maternal outcomes established using Delphi surveys. The secondary outcome was the composite of fetal and neonatal complications.

ANALYSIS

We developed two prediction models: a logistic regression model (PREP-L) to assess the overall risk of any maternal outcome until postnatal discharge and a survival analysis model (PREP-S) to obtain individual risk estimates at daily intervals from diagnosis until 34 weeks. Shrinkage was used to adjust for overoptimism of predictor effects. For internal validation (of the full models in the development data) and external validation (of the reduced models in the transportability data), we computed the ability of the models to discriminate between those with and without poor outcomes (c-statistic), and the agreement between predicted and observed risk (calibration slope).

RESULTS

The PREP-L model included maternal age, gestational age at diagnosis, medical history, systolic blood pressure, urine protein-to-creatinine ratio, platelet count, serum urea concentration, oxygen saturation, baseline treatment with antihypertensive drugs and administration of magnesium sulphate. The PREP-S model additionally included exaggerated tendon reflexes and serum alanine aminotransaminase and creatinine concentration. Both models showed good discrimination for maternal complications, with anoptimism-adjusted c-statistic of 0.82 [95% confidence interval (CI) 0.80 to 0.84] for PREP-L and 0.75 (95% CI 0.73 to 0.78) for the PREP-S model in the internal validation. External validation of the reduced PREP-L model showed good performance with a c-statistic of 0.81 (95% CI 0.77 to 0.85) in PIERS and 0.75 (95% CI 0.64 to 0.86) in PETRA cohorts for maternal complications, and calibrated well with slopes of 0.93 (95% CI 0.72 to 1.10) and 0.90 (95% CI 0.48 to 1.32), respectively. In the PIERS data set, the reduced PREP-S model had a c-statistic of 0.71 (95% CI 0.67 to 0.75) and a calibration slope of 0.67 (95% CI 0.56 to 0.79). Low gestational age at diagnosis, high urine protein-to-creatinine ratio, increased serum urea concentration, treatment with antihypertensive drugs, magnesium sulphate, abnormal uterine artery Doppler scan findings and estimated fetal weight below the 10th centile were associated with fetal complications.

CONCLUSIONS

The PREP-L model provided individualised risk estimates in early-onset pre-eclampsia to plan management of high- or low-risk individuals. The PREP-S model has the potential to be used as a triage tool for risk assessment. The impacts of the model use on outcomes need further evaluation.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN40384046.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Prediction of complications in early-onset pre-eclampsia (PREP): development and external multinational validation of prognostic models

BACKGROUND

Unexpected clinical deterioration before 34 weeks gestation is an undesired course in early-onset pre-eclampsia. To safely prolong preterm gestation, accurate and timely prediction of complications is required.

METHOD

Women with confirmed early onset pre-eclampsia were recruited from 53 maternity units in the UK to a large prospective cohort study (PREP-946) for development of prognostic models for the overall risk of experiencing a complication using logistic regression (PREP-L), and for predicting the time to adverse maternal outcome using a survival model (PREP-S). External validation of the models were carried out in a multinational cohort (PIERS-634) and another cohort from the Netherlands (PETRA-216). Main outcome measures were C-statistics to summarise discrimination of the models and calibration plots and calibration slopes.

RESULTS

A total of 169 mothers (18%) in the PREP dataset had adverse outcomes by 48 hours, and 633 (67%) by discharge. The C-statistics of the models for predicting complications by 48 hours and by discharge were 0.84 (95% CI, 0.81-0.87; PREP-S) and 0.82 (0.80-0.84; PREP-L), respectively. The PREP-S model included maternal age, gestation, medical history, systolic blood pressure, deep tendon reflexes, urine protein creatinine ratio, platelets, serum alanine amino transaminase, urea, creatinine, oxygen saturation and treatment with antihypertensives or magnesium sulfate. The PREP-L model included the above except deep tendon reflexes, serum alanine amino transaminase and creatinine. On validation in the external PIERS dataset, the reduced PREP-S model showed reasonable calibration (slope 0.80) and discrimination (C-statistic 0.75) for predicting adverse outcome by 48 hours. Reduced PREP-L model showed excellent calibration (slope: 0.93 PIERS, 0.90 PETRA) and discrimination (0.81 PIERS, 0.75 PETRA) for predicting risk by discharge in the two external datasets.

CONCLUSIONS

PREP models can be used to obtain predictions of adverse maternal outcome risk, including early preterm delivery, by 48 hours (PREP-S) and by discharge (PREP-L), in women with early onset pre-eclampsia in the context of current care. They have a potential role in triaging high-risk mothers who may need transfer to tertiary units for intensive maternal and neonatal care.

TRIAL REGISTRATION

ISRCTN40384046 , retrospectively registered.

Development and validation of prediction models for risk of adverse outcomes in women with early-onset pre-eclampsia: protocol of the prospective cohort PREP study

BACKGROUND

Early-onset pre-eclampsia with raised blood pressure and protein in the urine before 34 weeks' gestation is one of the leading causes of maternal deaths in the UK. The benefits to the child from prolonging the pregnancy need to be balanced against the risk of maternal deterioration. Accurate prediction models of risks are needed to plan management.

METHODS

We aim to undertake a multicentre prospective cohort study (Prediction of Risks in Early onset Pre-eclampsia (PREP)) to develop clinical prediction models in women with early-onset pre-eclampsia, for risk of adverse maternal outcomes by 48 h and by discharge. We will externally validate the models in two independent cohorts with 634 and 216 women. In the secondary analyses, we will assess risk of adverse fetal and neonatal outcomes at birth and by discharge.

DISCUSSION

The PREP study will quantify the risk of maternal complications at various time points and provide individualised estimates of overall risk in women with early-onset pre-eclampsia to plan the management.

TRIAL REGISTRATION

ISRCTN registry, ISRCTN40384046.