Study of serum uric acid and creatinine in hypertensive disorders of pregnancy

Endostatin and Cystatin C as Potential Biomarkers for Early Prediction of Preeclampsia

Preeclampsia (PE) is characterized by new onset hypertension and proteinuria. Undoubtedly, some individuals do not fit precisely into this description, and it could be challenging to spot newly developed PE in females who already have hypertension or renal illness. Monitoring the disease's progression enables the optimization of delivery time while minimizing premature births. The current study explores the diagnostic benefits of serum endostatin and cystatin C in addition to serum and urinary magnesium (Mg) and fractional excretion magnesium (FEMg) for early prediction of PE. The population sample included 82 pregnant women divided into 3 groups: normal pregnancy group served as a control (n = 26), nonpreeclampsia (NPE, n = 34) group included pregnant women with one or more risk factors but did not progress to PE, and pregnant women who developed preeclampsia (PE, n = 22) group. Blood samples were withdrawn at two sampling times: at 12th to 16th and 24th to 26th weeks of gestation. Compared to normal pregnancy, results (X̅ ± SD) indicated a significant increase in serum endostatin in NPE at the first sample (10.78 ± 3.63 ng/mL) and the second sample (28.03 ± 3.79 ng/mL), while cystatin C was at the first sample (0.68 ± 0.06 mg/dL) and the second sample (0.71 ± 0.07 mg/dL). In the PE group, the serum endostatin was 18.86 ± 4.37 ng/mL at the first sampling time and 53.56 ± 9.76 ng/mL for the second sample. Serum cystatin C was also elevated in PE with X̅ ± SD equivalent to 0.73 ± 0.08 and 0.89 ± 0.08 mg/dL at the first and second samples, respectively. On the other hand, serum and urinary Mg in addition to FEMg levels did not significantly differ across the groups under study. Receiver operating characteristic (ROC) curve analysis proved that both endostatin and cystatin C could be good indicators for PE. The findings imply that measuring endostatin and cystatin C at early pregnancy and before progression to PE may be effective in detecting the likelihood of PE. Endostatin could be more precise and sensitive in assessing the probability of PE than cystatin C; however, coupling of the two parameters may be promising.

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.

The Diagnostic Value of Hepatic and Renal Biochemical Tests for the Detection of Preeclampsia Among Pregnant Women Attending the Antenatal Care Clinic at the University of Gondar Comprehensive Specialized Hospital, Gondar, Northwest Ethiopia

Background

Preeclampsia has a deleterious effect on renal and liver function, which results in alterations of various biochemical tests. Therefore, the main aim of this study was to evaluate the role of some hepatic and renal biochemical tests in the diagnosis of preeclampsia.

Methods

A comparative cross-sectional study was carried out on a total of 126 pregnant women after 20th week of gestation who attended at the University of Gondar Comprehensive Specialized Hospital. The participants were divided into two groups as cases and controls. The case group consisted of 63 preeclamptic women, whereas the control group had 63 age and gestational week matched normotensive pregnant women. From each participant, three milliliters of blood was collected, the serum part was separated, and selected biochemical tests were measured using Humastar 800 chemistry analyzer. An independent t-test and receiver operating characteristics were done using SPSS 20 for comparison and diagnostic value determination of different biochemical tests between the study groups.

Results

The maternal serum aminotransferases, total bilirubin, Creatinine, and Urea levels were all significantly elevated in preeclamptic women compared to normotensive pregnant women. The receiver operating characteristics plots revealed that serum aspartate aminotransferase level had area under the curve of 0.89 (95% CI: 0.84–0.95) and can distinguish preeclampsia patients from normotensive pregnant women at cut-off value of ≥58.5 U/l with 74.6% sensitivity, 87.3% specificity, and 80.9% diagnostic accuracy. Serum Creatinine level had area under the curve of 0.91 (95% CI: 0.86–0.96), which enabled to indicate preeclampsia at a cut-off value ≥0.90 mg/dl with 77.8% sensitivity and 85.7% specificity.

Conclusion

An increased serum aminotransferases, total bilirubin, creatinine, and Urea levels in pregnant women could indicate the development of preeclampsia, and needs to be investigated. Among biochemical tests, serum Creatinine level was the best diagnostic marker of preeclampsia, followed by serum aspartate aminotransferase level.

The diagnostic potential of oxidative stress biomarkers for preeclampsia: systematic review and meta-analysis

Background

Preeclampsia is a multifactorial cardiovascular disorder of pregnancy. If left untreated, it can lead to severe maternal and fetal outcomes. Hence, timely diagnosis and management of preeclampsia are extremely important. Biomarkers of oxidative stress are associated with the pathogenesis of preeclampsia and therefore could be indicative of evolving preeclampsia and utilized for timely diagnosis. In this study, we conducted a systematic review and meta-analysis to determine the most reliable oxidative stress biomarkers in preeclampsia, based on their diagnostic sensitivities and specificities as well as their positive and negative predictive values.

Methods

A systematic search using PubMed, ScienceDirect, ResearchGate, and PLOS databases (1900 to March 2021) identified nine relevant studies including a total of 343 women with preeclampsia and 354 normotensive controls.

Results

Ischemia-modified albumin (IMA), uric acid (UA), and malondialdehyde (MDA) were associated with 3.38 (95% CI 2.23, 4.53), 3.05 (95% CI 2.39, 3.71), and 2.37 (95% CI 1.03, 3.70) odds ratios for preeclampsia diagnosis, respectively. The IMA showed the most promising diagnostic potential with the positive predictive ratio (PPV) of 0.852 (95% CI 0.728, 0.929) and negative predictive ratio (NPV) of 0.811 (95% CI 0.683, 0.890) for preeclampsia. Minor between-study heterogeneity was reported for these biomarkers (Higgins’ I² = 0–15.879%).

Conclusions

This systematic review and meta-analysis identified IMA, UA, and MDA as the most promising oxidative stress biomarkers associated with established preeclampsia. IMA as a biomarker of tissue damage exhibited the best diagnostic test accuracy. Thus, these oxidative stress biomarkers should be further explored in larger cohorts for preeclampsia diagnosis.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13293-022-00436-0.

Biomarkers of oxidative stress are related to the pathogenesis of preeclampsia and might be indicative of evolving preeclampsia and utilized for timely diagnosis and management of preeclampsia.

Systematic review and meta-analysis were conducted to evaluate the diagnostic accuracy of oxidative stress markers based on their diagnostic sensitivities and specificities.

Clinically relevant positive predictive values (PPVs) and negative predictive values (NPVs) were determined for each biomarker.

IMA, UA, and MDA were associated with 3.38, 3.05, and 2.37 odds ratios for preeclampsia onset.

IMA exhibited the most promising diagnostic potential with an average PPV of 0.852 and NPV of 0.811, respectively. Minor heterogeneity was reported for these biomarkers (Higgins’ I² = 0–15.879%).

These oxidative stress markers should be further explored in larger cohorts for preeclampsia diagnosis.

Increased Uric Acid, Gamma-Glutamyl Transpeptidase and Alkaline Phosphatase in Early-Pregnancy Associated With the Development of Gestational Hypertension and Preeclampsia

Background: Previous studies have reported that biomarkers of liver injury and renal dysfunction were associated with hypertensive disorders of pregnancy (HDP). However, the associations of these biomarkers in early pregnancy with the risk of HDP and longitudinal blood pressure pattern during pregnancy were rarely investigated in prospective cohort studies. Methods: A total of 1,041 pregnant women were enrolled in this prospective cohort study. BP was assessed in four stages throughout pregnancy. The following biomarkers were measured at early pregnancy before 18 weeks gestation: lactate dehydrogenase (LDH), aspartate aminotransferase to alanine aminotransferase ratio (AST/ALT), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), uric acid (UA), and estimated glomerular filtration rate (eGFR). Linear mixed-effects and logistic regression models were used to examine the associations of these biomarkers with longitudinal BP pattern during pregnancy and HDP incidence, respectively. Results: In unadjusted models, higher serum UA, GGT, ALP, and LDH levels, as well as lower eGFR and AST/ALT, were associated with higher BP levels during pregnancy and an increased risk of HDP. After adjustment for maternal age, pre-pregnancy BMI and other potential confounders, UA, GGT, ALP, and LDH remained positively associated with both BP and HDP. However, eGFR and AST/ALT were not associated with HDP after adjusting for potential confounders. When including all 6 biomarkers simultaneously in multivariable analyses, increased UA, GGT, and ALP significantly associated with gestational hypertension and preeclampsia. Conclusion: This study suggests that increased UA, GGT, and ALP in early-pregnancy are independent risk factors of gestational hypertension and preeclampsia.

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.

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.

Direct laboratory evidence that pregnancy-induced hypertension might be associated with increased catecholamines and decreased renalase concentrations in the umbilical cord and mother’s blood

Background

Renalase (RNL) is a controversial enzyme as to whether it oxidizes catecholamines (CAs) (as is generally accepted) in the blood or not. CAs (dopamine [DPMN], epinephrine [EPI] and norepinephrine [NEPI]) are associated with hypertension, including pregnancy-induced hypertension, which occurs in 8–10% of all pregnancies. Therefore, the aim of the study was to compare CAs and renalase concentration in (i) normotensive controls (C), (ii) patients with preeclampsia (PE) and (iii) patients with severe preeclampsia (SPE), which is one of the well-known symptoms of hypertension.

Methods

This case-control study involved 90 women divided into three groups – 30 C, 30 PE and 30 SPE – whose age and body mass indexes (BMIs) were similar. A total of 270 blood samples (90 maternal samples, 90 umbilical cord artery samples and 90 umbilical cord vein samples) were obtained. CAs and RNL concentrations of the biological samples were measured by enzyme-linked immunosorbent assay (ELISA).

Results

Comparing the amounts of CAs, RNL and systolic blood pressure (SBP)/diastolic blood pressure (DBP) between healthy control pregnant women and pregnant women with PE and SPE (SBP/DBP was 120/80 mm Hg for C, above 140/90 mm Hg for PE and above 160/110 mm Hg for SPE), the levels of CAs were significantly increased whereas RNL was reduced. The correlation between SBP/DBP and the amount of RNL in pregnant women with PE and SPE was negative.

Conclusions

These novel results are evidence that hypertension seen in PE and SPE is directly related to increased levels of CAs and reduced RNL concentrations. The use of RNL preparations may be preferred in future to prevent maternal and perinatal morbidity and mortality due to pregnancy-induced hypertension.

Maternal serum uric acid and calcium as predictors of hypertensive disorder of pregnancy: A case control study

OBJECTIVES

Compare serum uric acid and calcium levels among normotensive and hypertensive pregnant women, to compare maternal and perinatal outcomes in two groups.

MATERIALS AND METHODS

Prospective case control study was conducted after ethical approval in Obstetrics and Gynaecology department of rural tertiary care centre of Northern India, over seven months. Total 220 antenatal women ≥34 weeks of gestation with 110 cases having hypertensive disorder of pregnancy and 110 controls with normal blood pressure were compared for maternal uric acid and calcium levels and maternal, perinatal outcomes.

RESULTS

Mean ± SD values of uric acid and calcium in control group was 4.42 ± 1.42 mg/dl and 8.94 ± 0.6 mg/dl, whereas in cases they were 6.8 ± 2.72 mg/dl and 8.61 ± 0.78 mg/dl (p < 0.05). Induced labour followed by lower segment caesarean section was the most common mode of delivery in hypertensive cases, whereas, in controls, the majority had spontaneous onset of labour and delivered vaginally (p < 0.05). Hypertensive women with higher uric acid and lower calcium had adverse perinatal outcome as compared to controls (p < 0.05). Mean ± SD of neonatal birth weight in controls was 2.81 ± 0.295 Kg and in cases 2.56 ± 0.421 Kg. Neonatal birth weight was significantly associated with maternal uric acid than calcium in hypertensive women. Cases with hyperuricemia and low calcium levels had adverse overall outcome as compared to controls.

CONCLUSION

Maternal hyperuricemia and hypocalcaemia was associated with adverse maternal, perinatal outcomes in women with hypertensive disorder of pregnancy as compared to healthy normotensive women.

Biochemical Assessment of Renal and Liver Function among Preeclamptics in Lagos Metropolis

Objectives

Preeclampsia is a pregnancy specific syndrome. Studies have shown that preeclampsia has multiorgan dysfunction effects. This study evaluated biomarkers of renal and liver function among preeclamptic Nigerian women.

Study Design

This was a cross-sectional study conducted among 49 preeclamptic women and 50 normotensive healthy pregnant women.

Method

The baseline data comprising age, gestational age, and blood pressure were obtained. Venous blood and spot urine samples were collected from each participant. Plasma obtained from blood samples taken into lithium heparinized vacutainer bottles was assayed for electrolytes, urea, creatinine, total protein, albumin, and uric acid, while sera samples from blood samples taken into serum separation tube- (SST-) gel vacutainer were assayed for aspartate transaminase and alanine transaminase using ion selective electrode technique and Cobas autoanalyzer. Spot urine samples were assayed for protein and creatinine using Pyrogallol's reagent and Jaffe's methods, respectively. Microalbuminuria (protein/creatinine ratio) was generated from spot urine protein and creatinine data.

Result

The plasma sodium, total protein, and albumin in preeclamptic group were significantly decreased (p<0.05) when compared with control. There was statistically significant increase (p<0.05) in microalbuminuria, plasma potassium, urea, creatinine, uric acid levels, serum AST, and ALT activities in preeclamptic group. A positive association (p<0.05) between alanine aminotransferase and biomarkers of renal function was observed.

Conclusion

Preeclampsia has deleterious effects on renal and liver function as shown by alteration of these parameters.