Plasma antithrombin III levels in pre-eclampsia and chronic hypertension

New Ideas for the Prevention and Treatment of Preeclampsia and Their Molecular Inspirations

Preeclampsia (PE) is a pregnancy-specific disorder affecting 4-10% of all expectant women. It greatly increases the risk of maternal and foetal death. Although the main symptoms generally appear after week 20 of gestation, scientific studies indicate that the mechanism underpinning PE is initiated at the beginning of gestation. It is known that the pathomechanism of preeclampsia is strongly related to inflammation and oxidative stress, which influence placentation and provoke endothelial dysfunction in the mother. However, as of yet, no "key players" regulating all these processes have been discovered. This might be why current therapeutic strategies intended for prevention or treatment are not fully effective, and the only effective method to stop the disease is the premature induction of delivery, mostly by caesarean section. Therefore, there is a need for further research into new pharmacological strategies for the treatment and prevention of preeclampsia. This review presents new preventive methods and therapies for PE not yet recommended by obstetrical and gynaecological societies. As many of these therapies are in preclinical studies or under evaluation in clinical trials, this paper reports the molecular targets of the tested agents or methods.

Coagulation inhibitors in preeclamptic pregnant women

OBJECTIVE

Our objective was to detect clinical evaluation of coagulation inhibitors in preeclamptic and normotensive pregnant women and to determine their important role in pathogenesis of preeclampsia.

METHODS

A total of 20 mild, 20 severe preeclamptic and 45 normotensive pregnant women were included in this study. The plasma value of antithrombin III (AT-III) activity, proteins C and S activity, PT, PTT, fibrinogen and platelet counts were determined.

RESULTS

The values AT-III were lower in women with severe preeclampsia than in controls (p<0.05). In all groups, there was no significantly difference in the concentration of protein C activity, protein S and fibrinogen (p>0.05). The plasma thrombocyte counts were significantly lower in severe preeclamptic women than in normotensive women (p<0.05). There was no significant difference in the prothrombin time value in all groups, but a significantly difference with regard to partial thromboplastin time between severe preeclamptic and the control group (p<0.0001). It was longer than the control.

CONCLUSION

The markers of hemostasis activation such as protein S, protein C activity together with fibrinogen levels are not useful tools but the reduction of AT-III and platelet counts would seem useful in different pathological situations in pregnancy to predict and monitor the severity of the condition.

Fibronectin and antithrombin as markers of pre-eclampsia in pregnancy

INTRODUCTION

The differential diagnosis between pre-eclampsia and chronic hypertension is not easy, but is essential to proper management of a pregnancy. Patients presenting pre-pregnancy hypertension can be treated conservatively, if not a superimposed pre-eclampsia occurs, controlling pressure pharmacologically and completing the pregnancy with a natural delivery. In pre-eclampsia, hypertension is merely the visible sign of a process of endothelial damage and coagulation cascade activation which is often destined to emerge clinically on a dramatic scale.

MATERIALS AND METHODS

The study involved 18 women with physiological pregnancies, 19 with pre-eclampsia and 13 with chronic hypertension since superimposed pre-eclampsia. The following laboratory tests were performed: PT, PTT, AT-III, proteins C and S, platelet count, D-dimer, fibrinogen and plasma fibronectin. The three groups were compared using the Kruskall Wallis test, the median test and, for multiple comparisons, the Mann-Whitney test. A 'P' value of < 0.01 was considered as statistically significant.

RESULTS

The values for plasma fibronectin were higher in the pre-eclampsia group (410 mg/l (253-727)) than in controls (262 mg/l (183-385)) (P < 0.01) and values for AT-III were lower in the pre-eclampsia group (73% (40-100)) than in controls (93% (80-126) (P < 0.01) (Table 2). The groups with chronic hypertension revealed no such significant differences, however, in relation to the control group (fibronectin = 296 mg/l (198-530), AT-III = 86% (75-103)).

CONCLUSIONS

Measuring antithrombin and fibronectin to monitor any onset of pre-eclampsia can help the obstetrician to avoid important diagnostic and therapeutic errors.

Clotting inhibitors and fibronectin as potential markers in preeclampsia

OBJECTIVES

As conventional laboratory tests fail to identify early preeclampsia, the aim of this study was to seek a marker of endothelial injury and select more sensitive tests for monitoring the activation of the coagulation cascade.

METHODS

Using routine blood sampling methods, PT, PTT, AT-III, proteins C and S, platelets, fibrinogen and fibronectin were measured in 18 preeclamptic patients and 17 controls with a normal pregnancy.

RESULTS

Preeclampsia was associated with higher fibronectin and lower AT-III, protein C and protein S. The platelet count, fibrinogen and PT were similar. PTT was longer in preeclampsia.

CONCLUSION

As AT-III revealed compensated coagulopathy and fibronectin demonstrated preeclamptic vascular lesions before these were apparent from routine tests, measuring these elements could contribute to the earlier diagnosis and better treatment of chronically-altered coagulation in preeclampsia.

The value of antithrombin-III and fibronectin in hypertensive disorders of pregnancy

In this study we evaluated fibronectin as a marker of endothelial cell injury and antithrombin III as a marker of chronic activation of intravascular coagulation. The aim of the study was to establish to normal trends of plasma antithrombin III and fibronectin in general obstetric population and to determine the value of both in predicting, distinguishing and understanding the pathophysiology of pregnancy induced hypertension. The all cases consisted of 173 pregnant, 19 of them were chronic hypertensive, 45 were pregnancy induced hypertensive and 119 were normotensive at blood sampling. Out of 119 normotensive cases, 109 cases had no adverse outcome during their pregnancy. These cases were used as a control group and for the normal trends of antithrombin III and fibronectin in general obstetric population. Ten out of 119 cases who developed preeclampsia during follow up, 19 cases with chronic hypertension and 45 cases with pregnancy induced hypertension consisted of the study group. In the cases who developed preeclampsia during follow up, the value of plasma fibronectin level (above 95% confidence limit for that gestational week) to predict preeclampsia had 90% sensitivity and 94.4% specificity. In distinguishing hypertensive disorders of pregnancy (chronic hypertension or pregnancy induced hypertension) fibronectin had 71.1% sensitivity and 100% specificity. Plasma antithrombin III level (of antigenicity) measured by immunodiffusion method had no value in predicting and distinguishing pregnancy induced hypertension.