Risk Indicators for Eclampsia in Gestational Hypertension or Mild Preeclampsia at Term

Abnormal uterine inflammation in obstetric syndromes: molecular insights into the role of chemokine decoy receptor D6 and inflammasome NLRP3

The adaptation of the uterine environment into a favorable immunological and inflammatory milieu is a physiological process needed in normal pregnancy. A uterine hyperinflammatory state, whether idiopathic or secondary to hormonal or organic uterine disorders (polycystic ovary syndromes, endometriosis/adenomyosis and fibroids), negatively influences the interactions between decidua and trophoblast, early in gestation, and between chorion and decidua later in pregnancy. Abnormal activation of uterine inflammatory pathways not only contributes to the pathogenesis of the obstetric syndromes, i.e. recurrent pregnancy loss (RPL), pre-term delivery (PTD) and pre-eclampsia (PE), but also to correlates with severity. In this review, we summarize recent advances in the knowledge of uterine molecular mechanisms of inflammatory modulation in normal pregnancy and obstetric syndromes (RPL, PTD and PE). In particular, we focus on two regulators of uterine/placental inflammation: the NLRP3 inflammasome and the chemokines decoy receptor D6. We performed comprehensive review of the literature in PubMed and Google Scholar databases from 1994 to 2018. The available evidence suggests that: (i) the expression of inflammasome NLRP3 is increased in the endometrium of women with unexplained RPL, in the chorioamniotic membranes of women with PTL and in the placenta of women with PE; (ii) there is a role for abnormal expression and function of D6 decoy receptor at the feto-maternal interface in cases of RPL and PTD and (iii) the function of placental D6 decoy receptor is impaired in PE. A wider comprehension of the inflammatory molecular mechanisms involved in the pathogenesis of the obstetric syndromes might lead to the identification of new potential therapeutic targets.

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.

First versus second trimester mean platelet volume and uric acid for prediction of preeclampsia in women at moderate and low risk

OBJECTIVE

To determine if second trimester mean platelet volume (MPV) and serum uric acid are reasonable predictors of preeclampsia (PE) or not, in patients at moderate and low risk.

METHODS

This prospective study was conducted on 9522 women at low or moderate risk for developing PE who underwent dual measurements of MPV and serum uric acid at late first trimester (10-12 weeks) and at second trimester (18-20 weeks) and subsequently divided into two groups; PE group (n = 286) who later developed PE and non-PE group (n = 9236). Test validity of MPV and serum uric acid was the primary outcome measure. Data were collected and analyzed.

RESULTS

Second trimester MPV is a good predictor for development of PE at a cutoff value of 9.55 fL with area under the curve (AUC) of 0.86, sensitivity of 95.2%, specificity of 66.7%, positive predictive value (PPV) of 87%, negative predictive value (NPV) of 85.7%, and accuracy of 86.7%. Second trimester serum uric acid is a good predictor for development of PE at a cutoff value of 7.35 mg/dL, with AUC of 0.85, sensitivity of 95.2%, specificity of 55.6%, PPV of 83.3%, NPV of 83.3%, and accuracy of 83.3%. Combination of both tests has a sensitivity of 100%, specificity of 22.2%, PPV of 75%, NPV of 100%, and accuracy of 76.7%.

CONCLUSION

Second trimester MPV and serum uric acid alone or in combination could be used as a useful biochemical markers for prediction of PE based on their validity, simplicity, and availability.

Pre-eclampsia

Pre-eclampsia affects 3-5% of pregnancies and is traditionally diagnosed by the combined presentation of high blood pressure and proteinuria. New definitions also include maternal organ dysfunction, such as renal insufficiency, liver involvement, neurological or haematological complications, uteroplacental dysfunction, or fetal growth restriction. When left untreated, pre-eclampsia can be lethal, and in low-resource settings, this disorder is one of the main causes of maternal and child mortality. In the absence of curative treatment, the management of pre-eclampsia involves stabilisation of the mother and fetus, followed by delivery at an optimal time. Although algorithms to predict pre-eclampsia are promising, they have yet to become validated. Simple preventive measures, such as low-dose aspirin, calcium, and diet and lifestyle interventions, show potential but small benefit. Because pre-eclampsia predisposes mothers to cardiovascular disease later in life, pregnancy is also a window for future health. A collaborative approach to discovery and assessment of the available treatments will hasten our understanding of pre-eclampsia and is an effort much needed by the women and babies affected by its complications.

Prognostic models in obstetrics: available, but far from applicable

Health care provision is increasingly focused on the prediction of patients' individual risk for developing a particular health outcome in planning further tests and treatments. There has been a steady increase in the development and publication of prognostic models for various maternal and fetal outcomes in obstetrics. We undertook a systematic review to give an overview of the current status of available prognostic models in obstetrics in the context of their potential advantages and the process of developing and validating models. Important aspects to consider when assessing a prognostic model are discussed and recommendations on how to proceed on this within the obstetric domain are given. We searched MEDLINE (up to July 2012) for articles developing prognostic models in obstetrics. We identified 177 papers that reported the development of 263 prognostic models for 40 different outcomes. The most frequently predicted outcomes were preeclampsia (n = 69), preterm delivery (n = 63), mode of delivery (n = 22), gestational hypertension (n = 11), and small-for-gestational-age infants (n = 10). The performance of newer models was generally not better than that of older models predicting the same outcome. The most important measures of predictive accuracy (ie, a model's discrimination and calibration) were often (82.9%, 218/263) not both assessed. Very few developed models were validated in data other than the development data (8.7%, 23/263). Only two-thirds of the papers (62.4%, 164/263) presented the model such that validation in other populations was possible, and the clinical applicability was discussed in only 11.0% (29/263). The impact of developed models on clinical practice was unknown. We identified a large number of prognostic models in obstetrics, but there is relatively little evidence about their performance, impact, and usefulness in clinical practice so that at this point, clinical implementation cannot be recommended. New efforts should be directed toward evaluating the performance and impact of the existing models.

Uric acid: is it time to give up routine testing in management of pre-eclampsia?

Ever since it was first linked with the pathophysiology of pre-eclampsia, uric acid has been a routine test requested by many care-givers managing pregnant women with hypertensive disease of pregnancy for almost 100 years. Existing evidence however suggests that it has no definitive role in prediction, diagnosis or management of pre-eclampsia. We argue against routine uric acid testing in pregnancies complicated by hypertension not only because it has become a fruitless academic exercise but also because ceasing its routine use will ensure cost-savings for the health services.

Association of uric acid with progression to preeclampsia and development of adverse conditions in gestational hypertensive pregnancies

BACKGROUND

Preeclampsia is a serious pregnancy complication. Gestational hypertension is a common first clinical presentation of preeclampsia. Little is known about which clinical risk factors are associated with the progression from gestational hypertension to preeclampsia.

METHODS

In a retrospective cohort study of 249 singleton pregnant women with an initial presentation of gestational hypertension in an obstetric hospital, we assessed which routinely available clinical risk factors are associated with the progression to preeclampsia and the development of adverse maternal or infant conditions.

RESULTS

The mean serum uric acid level at the initial presentation of gestational hypertension was significantly higher comparing patients who later progressed to preeclampsia to those who did not (5.06 vs. 4.59 mg/dl, P < 0.01). Lower gestational age and higher serum uric acid level at the initial presentation of gestational hypertension and subsequent need for antihypertensive drug treatment for blood pressure (BP) control were associated with significantly increased risks of progression to preeclampsia, and development of adverse maternal or infant conditions. One standard deviation (s.d.) increase in serum uric acid level was associated with 2.3-fold increased odds of progression to preeclampsia (adjusted odds ratio (aORs) 2.33 (95% confidence interval (CI) 1.45-3.74)), and 1.5-fold increased odds of developing clinically significant adverse maternal or infant conditions (aOR 1.49 (1.03-2.17)) irrespective of the progression to preeclampsia.

CONCLUSIONS

Higher serum uric acid levels at the initial presentation of gestational hypertension may indicate heightened risk of progression to preeclampsia and development of adverse maternal/infant conditions.