Activated protein C resistance and factor V Leiden in patients with hemolysis, elevated liver enzymes, low platelets syndrome

Factor-V Leiden G1691A and prothrombin G20210A polymorphisms in Sudanese women with preeclampsia, a case -control study

Background

Preeclampsia can lead to adverse maternal and perinatal outcomes. There are few studies on the association of preeclampsia with thrombophilia in Africa including Sudan.

Methods

A case –controls study was conducted at Saad Abualila Hospital in Khartoum, Sudan during the period of February through November 2017. The cases were women with preeclampsia and healthy pregnant women were the controls (180 women in each arm of the study). Genotyping for Factor-V Leiden 1691G/A and Prothrombin gene variation 20210G/A was done by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP).

Results

There was no significant difference in the age, parity, body mass index (BMI) and the other characteristics between the cases and the controls. Genotypes distribution of Factor V Leiden 1691G/A and prothrombin gene 20210G/A in controls was in accordance with the Hardy–Weinberg equilibrium (P > 0.05). The factor V Leiden-variation was present in 9.6% of the cases compared with 0.6% of the controls, P < 0.001 (OR = 18.60, 95% CI = 2.38–136.1). Only 4 patients with severe preeclampsia had homozygous variation A/A and it was not detected in the controls. Prothrombin G20210A variations not detected neither in the cases nor in the controls group.

Conclusions

High prevalence of Factor V Leiden 1691G/A variation in preeclamptic patients compared to controls suggest an involvement of this variation in predisposing to preeclampsia in this setting.

Antithrombotic therapy and pregnancy: consensus report and recommendations for prevention and treatment of venous thromboembolism and adverse pregnancy outcomes

Venous thromboembolism and adverse pregnancy outcomes are potential complications of pregnancy. Numerous studies have evaluated both the risk factors for and the prevention and management of these outcomes in pregnant patients. This consensus group was convened to provide concise recommendations, based on the currently available literature, regarding the use of antithrombotic therapy in pregnant patients at risk for venous thromboembolic events and adverse pregnancy outcomes.

Evaluation of natural coagulation inhibitor levels in various hypertensive states of pregnancy

OBJECTIVE

To evaluate the role of natural coagulation inhibitors in various classifications of pregnancy associated hypertension in Turkish population living in Trakya region of Turkey.

STUDY DESIGN

Serum uric acid levels, plasma protein C (PC), protein S (PS), antithrombin III (AT III) activities and activated protein C resistance (APCR) were measured in 80 pregnant women with hypertension (preeclampsia, n = 32; severe preeclampsia, n = 25; eclampsia, n = 14; chronic hypertension, n = 9) and 58 healthy pregnant women. Tukey and Tamhane multiple comparison tests, Kruskal-Wallis, chi2 and Fisher's exact tests were performed for comparison of means and/or medians.

RESULTS

Serum uric acid levels were significantly elevated in women with preeclampsia and severe preeclampsia, but PS activity decreased in women with severe preeclampsia (33.2 +/- 18.9% versus 50.4 +/- 22.7%, p = 0.015) and chronic hypertension (29.5 +/- 14.5% versus 50.4+ /- 22.7%, p = 0.045) compared to healthy controls. There was no significant difference in APCR, and PC or AT III activity between the groups. Platelet counts were significantly lower in women with severe preeclampsia, compared to controls and women with chronic hypertension.

CONCLUSION(S)

Serum uric acid levels and plasma protein S activity may be useful as indices of severity of pathology in pregnancy associated hypertension.

Inherited thrombophilias and adverse pregnancy outcome: screening and management

Inherited thrombophilias are a heterogenous group of conditions which have been implicated in a variety of pregnancy complications. Evidence is mounting that implicates these inherited disorders in a range of pregnancy outcomes, including recurrent miscarriage, late fetal loss, preeclampsia, abruptio placentae, and intrauterine growth restriction. The most commonly identified inherited thrombophilias consist of Factor V Leiden and the prothrombin gene mutation G20210A. Rarer inherited thrombophilic conditions include deficiencies of protein S, C and antithrombin. More recently, deficiency of protein Z has been linked to pregnancy complications, including preterm delivery. Clinical manifestations often are associated with the presence of more than one inherited thrombophilia, consistent with their multigenic nature. Some, but not all, studies investigating the use of heparin to prevent adverse pregnancy outcome have demonstrated a benefit. However, an adequate randomized trial is required to definitively determine whether heparin anticoagulation is the best prevention option in patients who harbor one or more inherited thrombophilias and are at risk for adverse pregnancy outcome. This review will summarize the association of thrombophilic conditions and obstetrical complications.

Screening and management of inherited thrombophilias in the setting of adverse pregnancy outcome

Inherited thrombophilic conditions are associated with adverse pregnancy outcomes, including severe pre-eclampsia, fetal loss, abruptio placentae, and intauterine growth restriction. Although the prevalence of these complications is approximately 8% in the general population, their presence is associated with a significantly increased recurrence risk. Thrombophilic conditions most strongly associated with adverse pregnancy outcome include factor V Leiden, prothrombin gene mutation, and deficiencies of protein S, protein C, and antithrombin. Other thrombophilic conditions, such as protein Z deficiency, also appear to be associated with an increased risk of pregnancy complications. Antenatal administration of heparin to prevent pregnancy complications has shown promise in small studies, but a randomized, placebo-controlled trial is necessary to determine whether heparin administration is beneficial in preventing adverse pregnancy outcome.

Thrombophilia and pregnancy

Pregnancy is hypercoagulable state. The field of thrombophilia; the tendency to thrombosis, has been developed rapidly and has been linked to many aspects of pregnancy. It is recently that severe pregnancy complications such as severe preeclampsia intrauterine growth retardation abruptio placentae and stillbirth has been shown to be associated with thrombophilia. Recurrent miscarriage and has also been associated with thrombophilia. Finally, thromboembolism in pregnancy as in the non-pregnant state is linked to thrombophilia. In this review all aspects of thrombophilia in pregnancy are discussed, and also all prophylactic and therapeutic implications.

Factor V Leiden: a review of the literature

Factor V Leiden, formed by a genetic mutation, disrupts the body's anticoagulation defense system. It was isolated as recently as 1994 as a risk factor for venous thromboembolism. Factor V Leiden has also been linked to preeclampsia, pregnancy loss, and fetal growth restriction. In addition, factor V Leiden has implications for women who are not pregnant. The most effective screening tool is a thorough personal and family history related to thrombosis. For women with a positive factor V Leiden screen, counseling regarding the risks of thrombosis is essential.

Heparin for pregnant women with acquired or inherited thrombophilias

BACKGROUND

Thrombophilias, which are associated with a predisposition to thrombotic events, have been implicated in adverse obstetrical outcomes such as intrauterine growth restriction, stillbirth, severe early onset pre-eclampsia, and placental abruption. Heparin administration in pregnancy may reduce the risk of these events.

OBJECTIVES

The objective of this review was to assess the effects of heparin on pregnancy outcomes for women with a thrombophilia.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register (July 2002), MEDLINE, EMBASE, CINAHL, Scidex (via OVID Technologies - July 2002) and reference lists and personal files.

SELECTION CRITERIA

Randomized controlled trials comparing heparin with placebo or no treatment, or randomized controlled trials comparing any two treatments. Quasi randomized studies would be included.

DATA COLLECTION AND ANALYSIS

Data would be abstracted from identified studies and recorded on a paper form by two reviewers.

MAIN RESULTS

No studies were included.

REVIEWER'S CONCLUSIONS

There are no completed trials to determine the effects of heparin on pregnancy outcomes for women with a thrombophilia.

Searching for preeclampsia genes: the current position

Although there is substantial evidence that preeclampsia has a genetic background, the complexity of the processes involved and the fact that preeclampsia is a maternal-fetal phenomenon does not make the search for the molecular basis of preeclampsia genes easy. It is possible that the single phenotype 'preeclampsia' in fact should be divided into different sub-groups on genetic or biochemical level. In the present review, the preeclampsia phenotype and its pathophysiologic features are discussed. Family studies and postulated inheritance models are summarized. A systematic overview is given on the numerous candidate gene studies and gene-expression studies performed so far and on the currently available genome-wide scan data. Despite extensive research the molecular genetic basis of preeclampsia remains unclear. Future studies will hopefully enhance our insights in the molecular pathogenesis of preeclampsia.

Is there an increased maternal-infant prevalence of Factor V Leiden in association with severe pre-eclampsia?

OBJECTIVE

To compare the prevalence of the Factor V Leiden mutation in children and maternal-infant pairs in pregnancies affected by severe pre-eclampsia with unmatched normal controls.

DESIGN

Prospective cohort study.

SETTING

Department of Women's and Children's Health, The Canberra Hospital, Garran, ACT, Australia.

SAMPLE

Forty-eight maternal-infant pairs where the index pregnancy was affected by severe pre-eclampsia; 46 unmatched maternal-infant pairs where the index pregnancy was defined as normal.

METHODS

DNA analysis of cheek swab samples obtained from maternal-infant pairs for the Factor V Leiden mutation.

MAIN OUTCOME MEASURE

The prevalence of the Factor V Leiden mutation in mothers, infants and maternal-infant pairs in association with severe pre-eclampsia compared with unmatched controls.

RESULTS

No difference was detected in the prevalence of Factor V Leiden mutation between the women and children of both groups, nor the maternal-infant pairs from each group.

CONCLUSIONS

No evidence was found of an increased prevalence of the Factor V Leiden mutation in either the mothers or children in association with severe pre-eclampsia. This result argues against a Factor V Leiden fetal or maternal contribution to the development of severe pre-eclampsia.

HELLP syndrome and factor V Leiden

The association of thrombophilia and obstetrical complications is documented and well consistent with the hypothesis of an insufficient placental perfusion due to fibrin deposition as a major underlying pathophysiological mechanism. Factor V Leiden is one of the most frequent thrombophilic mutations. A high prevalence of this mutation has recently been reported in a group of 21 German women with haemolysis, elevated liver enzymes, low platelets (HELLP) syndrome. In this respect, we studied the prevalence of factor V Leiden in 18 women who were consecutively diagnosed at our Department of Obstetrics and Gynaecology as having HELLP syndrome, between 1995 and 1999. Women were tested either at the time of diagnosis or months or years after delivery for coagulation parameters, protein C (PC), protein S (PS), antithrombin III, lupus-like anticoagulant, anticardiolipin antibodies (ACA), activated protein C (APC) resistance and detection of the G1691A mutation (factor V Leiden). In all women, the parameters studied were normal and in none of the investigated cases was the G1691A mutation found. HELLP being a severe form of preeclampsia, we think that the reported association between factor V Leiden and HELLP may reflect the well-known association with preeclampsia.

HELLP syndrome

HELLP syndrome is a serious, life-threatening form of pre-eclampsia with a typical laboratory triad. The incidence of the disease is reported as being 0.17-0.85% of all live births. There has been, to date, neither reliable early recognition nor effective prevention of HELLP syndrome. As a result of endothelial dysfunction, activation of intravascular coagulation occurs with fibrin deposition in the capillaries and consecutive microcirculation disorders. The disease manifests itself on average between 32-34 weeks' gestation. HELLP syndrome will occur postpartum in up to 30% of the cases. The clinical cardinal symptom of the disease is right upper quadrant pain or epigastric pain accompanied with nausea, vomiting and malaise. In 20% of the cases with HELLP syndrome there is no hypertension and 5-15% of the pregnant patients present a low level of proteinuria or none at all. The early recognition of hemolysis is most sensitively managed by the determination of the serum haptoglobin. The increase of the aspartate transaminase (AST) and the alanine transaminase (ALT) often precedes a decrease in platelets. The course of HELLP syndrome is incalculable. It is universally agreed that a pregnancy from 32-34 weeks should be immediately delivered. Before 32-34 weeks, expectant management is generally possible in a perinatal center. The frequency for a repeated hypertensive disease in pregnancy ranges from 27% to 48%.

Antithrombotic therapy in high-risk pregnancy

Venous thromboembolism remains a major cause of morbidity and mortality associated with pregnancy and puerperium. Specific risk factors for this disorder can be identified before or during pregnancy and delivery. The heritable defects believed to be associated with venous thrombosis are factor V Leiden mutation; elevated antiphospholipid antibodies; and deficiencies of antithrombin, protein C, and protein S. Women with a history of thromboembolism and thrombophilia should receive antenatal and postpartum thrombosis prophylaxis.

Maternal and neonatal outcome of preeclamptic pregnancies: the potential roles of factor V Leiden mutation and 5,10 methylenetetrahydrofolate reductase

OBJECTIVE

To investigate the potential perinatal effects of Factor V Leiden mutation and 5,10 methylenetetrahydrofolate reductase C677T polymorphism in preeclamptic women.

STUDY DESIGN

One hundred twenty preeclamptic women (N = 120) and 101 healthy pregnant controls (N = 101) were recruited and evaluated for frequency of Leiden and 5,10 methylenetetrahydrofolate reductase (MTHFR) mutations using polymerase chain reaction (PCR). Perinatal outcomes were then recorded and analyzed for all study participants and their neonates.

RESULTS

Laboratory analysis yielded 22 (18.33%) heterozygous carriers of Factor V Leiden mutation among preeclamptic women and 3 (2.97%) heterozygous carriers among the healthy controls; differences between the two groups were found to be statistically significant [p < 0.001, the relative risk (RR) = 6.17, 95% confidence interval (95% CI) = 1.90-20.02]. Homozygous MTHFR mutations were found in 8 of 120 (6.67%) preeclamptic women and in 6 of the 101 (5.94%) healthy controls evaluated. Among preeclamptic women, episodes of hemolysis, elevated liver enzymes, and low platelet (HELLP) syndrome were reported in 7 of 22 (31.81%) of those with Factor V Leiden mutation and in 11 of 98 (11.22%) of those who were negative for the mutation. Group differences were determined to be statistically significant (p < 0.015, RR = 2.83, 95% CI = 1.24-6. 48). Perinatal indicators collected from the two groups included frequency of intrauterine growth retardation, birth weight, and gestational age. No statistically different perinatal outcomes were found between Factor V Leiden positive and negative preeclamptic women. In addition, MTHFR gene polymorphism did not appear to be correlated with the development of preeclampsia.

CONCLUSION

Although the frequency of Factor V Leiden mutation appears to be significantly higher among preeclamptic women, the mechanism of pathogenesis and potential influence on perinatal outcomes is not yet well understood. Relatively high rates of HELLP syndrome among those with Factor V Leiden mutation suggest that this thrombogene mutation may play a significant role in hemostatic system activation. Our results suggest that the role of MTHFR polymorphism and other factors such as folic acid supplementation will require more extensive analysis in controlling worldwide morbidity and mortality associated with this important maternal condition.

Thromboembolic disease in pregnancy

Recent publications have produced some new estimates of the incidence of pregnancy-related venous thromboembolic disease, and have found increasing evidence of an association between inherited thrombophilias and pregnancy complications and fetal loss. The balance of benefit and risk of thromboprophylaxis remains to be evaluated, and studies are needed to provide a sound basis for clinical practice.

Obstetric implications of activated protein C resistance and factor V Leiden mutation

An increasing number of reports have focused on activated protein C resistance (APCR) as it has been shown not only to be the most common genetic factor predisposing patients to thromboembolic disease but the most common identifiable cause overall. More than 90 percent of the cases of APCR are caused by the factor V Leiden mutation, in which a guanine to adenine substitution in the factor V gene at nucleotide position 1691 results in a glutamine to arginine switch at position 506. Recent studies have also pointed to evidence of an association between APCR/factor V Leiden mutation and hypertensive disorders of pregnancy, first and second trimester miscarriage, placental infarction, and placental abruption.