Genetic prothrombotic risk factors in women with unexplained pregnancy loss

INTRODUCTION: Inherited thrombophilia has been associated with unexplained recurrent pregnancy loss (RPL) and stillbirth. This thrombotic tendency can manifest as thrombotic lesions in the placenta, and may lead to abortion and stillbirth. The aim of our case-control study was to investigate the prevalence of FVL and FII G20210A in women with adverse pregnancy outcome, compared to the prevalence of the same mutations in our health control group. MATERIALS AND METHODS: 102 consecutive women with unexplained pregnancy loss (55 with history of RPL, and 47 with history of stillbirth) were studied for hereditary thrombophilia. The health control group consisted of 217 healthy women from the general population. RESULTS AND CONCLUSIONS: Of the 55 women with recurrent abortions, we found the same prevalence for the FVL and the FII G20210A(9.1%, 5 pts). (p=NS compared to control group). Of the 47 women with stillbirth, 11 (23.4%) had the FVL and 9 (19.1%) had the FII G20210A(p<0.0005 for both mutations). In our experience the prevalence of FVL and the FII G20210Amutations was significantly higher in women with unexplained stillbirth, instead the prevalence of genetic thrombophilia was high but not statistically significant in women with recurrent pregnancy loss.     

Protein C levels in late pregnancy, postpartum and in women on oral contraceptives

4 groups of 30 women participated in a study designed to examine the protein C level during late normal pregnancy, the puerperal period, and oral contraceptive (OC) use. The results were compared with those obtained with another important inhibitor, i.e., antithrombin III. In pregnant women, protein C levels during the 3rd trimester of normal pregnancy were the same as those in control nonpregnant women. Delivery did not induce any variations in protein. Antithrombin III was slightly decreased in late pregnancy, the decrease being more important at 24 hours following delivery. The women using OCs showed a significant increase in protein C compared with the control group; antithrombin was similar in both groups. The results show that protein C levels were not altered in the 3rd trimester of normal pregnancy and in the immediate postpartum period and make it difficult to assign an important role to protein C in the mechanism responsible for the increased rick of thrombosis observed in these situations. The data also eliminate the possibility that the risk of thrombosis observed in OC users could be due to a decrease in protein C.     

Gestational outcome in thrombophilic women with recurrent pregnancy loss treated by enoxaparin

Inherited and acquired thrombophilia are associated with recurrent pregnancy loss (RPL). We have evaluated the efficacy and safety of the low molecular weight heparin enoxaparin in 50 women, (mean age 26 +/- 3 years) with RPL (> or =3 losses in 1st, > or =2 losses in 2nd and > or =1 loss in 3rd trimester) who were found to harbor thrombophilia. Twenty-seven had a solitary thrombophilic defect, and twenty-three women had combined thrombophilic defects: 17--two defects and 6--three defects. Following diagnosis of thrombophilia, sixty-one subsequent pregnancies were treated with the low molecular weight heparin enoxaparin throughout gestation until 4 weeks after delivery. Dosage was 40 mg/day in women with solitary defect and 80 mg/day in combined defects. Aspirin, 75 mg daily was given in addition to enoxaparin to women with antiphospholipid syndrome. Forty-six out of 61 (75%) gestations treated by enoxaparin resulted in live birth compared to only 38/193 (20%) of the untreated pregnancies in these 50 women prior to diagnosis of thrombophilia (p <0.00001). In 23 women without a single living child following 82 untreated gestations, antithrombotic therapy resulted in 26/31 (84%) successful deliveries (p <0.0001). In 20 women with a prior living child, antithrombotic therapy improved successful delivery from 33/86 (38%) to 20/21 (95%) (p <0.0001). Enoxaparin dose of 40 mg/day resulted in live birth in 24/35 (69%) of gestations, compared to 19/23 (83%) gestations in women treated with 80 mg/day (p = 0.37). Only one thrombotic episode and one mild-bleeding episode were noticed during enoxaparin therapy. Enoxaparin is safe and effective in prevention of pregnancy loss in women with inherited and acquired thrombophilia.     

Anti-beta2-glycoprotein I antibodies are associated with pregnancy loss in women with the lupus anticoagulant

The presence of lupus anticoagulant (LA) predisposes to fetal loss and to venous and arterial thrombosis; however, a subgroup of women is unaffected by pregnancy loss. Currently, no predictive markers are available for the identification of women positive for LA at increased risk for pregnancy loss. It was the aim of our study to investigate whether increased anti-beta2-GPI-antibodies predict pregnancy loss in women positive for LA. We performed a cross-sectional study in a cohort of 39 women with persistent LA, who had in total 111 pregnancies. Fifteen women had exclusively normal pregnancies (30 pregnancies) and 24 women had pregnancy losses (81 pregnancies). Anti-beta2-GPI-antibodies were determined using a semiquantitative enzyme linked immunoassay (QUANTA Lite beta2 GPI IgG and IgM; Inova Diagnostics). Increased levels of anti-beta2-GPI antibodies were significantly associated with pregnancy loss [odds ratio (OR) 9.6, 95% confidence interval (CI) 1.6-56.4]. This risk was even higher in the subgroup of women (n = 16) with more than two miscarriages or fetal loss after the first trimester [OR 13.1, 95% CI 1.4-126.3]. There was no significant association between anticardiolipin antibodies and pregnancy loss [OR 3.5, 95% CI 0.7-17.6]. The co-existence of anti-beta2-GPI and anticardiolipin antibodies was also predictive for pregnancy loss [OR 6.1, 95% CI 1.3-29.7]. Interestingly, the prevalence of thrombosis was similar between women with normal pregnancy (87%) and those with pregnancy loss (75%). We conclude that increased levels of anti-beta2-GPI antibodies are predictive for pregnancy loss among women positive for LA, and that prophylactic treatment should be considered in these women even without a history of previous pregnancy loss.     

Circulating procoagulant microparticles in women with unexplained pregnancy loss: a new insight

One of the frequently proposed mechanisms for pregnancy losses refers to uteroplacental thrombosis. However the contribution of classical thrombotic risk factors remains questionable and, if real, does not account for a large number of pregnancy losses. The aim of this study was to investigate the presence of circulating procoagulant microparticles, a new marker of cell activation already associated with various prothrombotic clinical settings. Microparticles were assessed by an original prothrombinase assay on platelet depleted plasma obtained from 74 women with a history of pregnancy loss without apparent cause and 50 controls. Patients were studied at least 2 months after the last obstetrical event and were classified into 2 groups: 49 women with at least 3 consecutive spontaneous abortions at or before the 10th postmenstrual week and 25 with at least one fetal death beyond the 10th postmenstrual week. Among the 74 patients, 41 had increased levels of circulating microparticles, 29 belonging to the group of early pregnancy loss (59%) and 12 to the group of late pregnancy loss (48%). The high prevalence of increased levels of procoagulant microparticles in both groups makes this new marker very promising for the understanding, follow up and therapeutical handling of pregnancy loss.     

Protein C functional assay using snake venom activator

We report a functional assay of Protein C on whole plasma using a snake venom called Protac-C. This method is simple, avoids absorption-elution techniques. Also this method can be adopted to a microtitre plate system testing of large number of samples. Functional levels by this test correlated well with the antigenic levels (r = .8) measured by ELISA. Protein C functional and antigenic values in 58 healthy volunteers were 82% and 95.5% respectively. The warfarinized samples showed a lower mean.     

Modulation of systemic hemostatic parameters by enoxaparin during gestation in women with thrombophilia and pregnancy loss

Recurrent pregnancy loss (PL) is associated with maternal thrombophilia and prophylaxis with low molecular weight heparin (LMWH) can improve pregnancy outcome in this setting.The aim of this study was to investigate the modulation of systemic hemostatic parameters by enoxaparin in women with recurrent PL and to evaluate plasmatic parameters that would potentially enable monitoring LMWH prophylaxis effect during pregnancy. Study group included 87 women with thrombophilia and PL treated with enoxaparin 40 mg daily vs. 40 mg twice daily. The control group comprised 40 women with normal pregnancies. Blood samples have been collected throughout the period starting at 5-10 weeks of gestation until 6-10 weeks postpartum. The determined plasmatic markers included: anti-Xa activity, total and free tissue factor pathway inhibitor (TFPI), D-dimer, prothrombin fragment 1+2 (PT1+2), activated protein C resistance (APC-SR) and free protein S. Successful pregnancy outcome was recorded in 70 (80.5%) women treated with enoxaparin, without correlation to enoxaparin dosage. Seventeen women (19.5%) had pregnancy loss at 16+/-7 (6-32) weeks of gestation. Anti-Xa levels at 10-15 weeks of gestation were higher (0.39+/-0.38 u/ml) in the successful pregnancy outcome group compared to the abortion group (0.22+/-0.2 u/ml). Prophylactic anti-Xa activity levels (0.28+/-0.13 u/ml) were documented from 15 weeks of gestation until delivery in the successful pregnancy outcome group. Significant increase in anti-Xa, total TFPI and free TFPI levels (P<0.001) was achieved after beginning of LMWH prophylaxis in successful pregnancy outcome group but not in the abortion group. D-dimer and PT1+2 levels appeared to be significantly increased while APC-SR and free protein S levels gradually decreased during pregnancy, with no difference between study groups. These results suggest that LMWH prophylaxis during pregnancy enables modulation of systemic hemostatic parameters via inhibition of factor Xa and increase in plasmatic total and free TFPI levels.     

Preeclampsia and pregnancy loss in women with a history of venous thromboembolism and prophylactic low-molecular-weight heparin (LMWH) during pregnancy

Limited data are available regarding complications of pregnancy and pregnancy outcome under prophylaxis with low-molecular-weight heparin (LMWH) in women with a history of thromboembolism (TE). We retrospectively evaluated pregnancy complications in a cohort of 80 women. All had a history of TE (76 venous, two arterial and two venous and arterial) and received prophylactic LMWH during 86 pregnancies. The rate of preeclampsia and stillbirth in these women was compared to that of a control group of 313 women without a history of TE and LMWH. Prophylaxis was started at a median of 10 weeks of gestation and usually continued until six weeks post partum. In 94% of the cases the outcome of pregnancy was favourable with a live birth. Four pregnancies (4.7%) ended in miscarriage. Two (2.3%) pregnancies were complicated by a thromboembolic event (one deep leg vein thrombosis and PRIND, respectively). One patient developed HELLP-syndrome. Severe preeclampsia occurred in three (3.8%) and stillbirth in one (1.3%) of the patients (n = 80), whereas this was the case in four (1.3%, odds ratio 3.01; 95% confidence interval (CI) 0.66-13.73, p = 0.15) and 10 (3.2%, OR = 0.38; 95% CI 0.05-3.04, p = 0.72) control women. Mean birth weight and standard deviation of infants was 3,160 +/- 930 g in patients and 3,300 +/- 540 g in controls (p = 0.11). We conclude that a favourable pregnancy outcome in women with a history of thromboembolism who use prophylactic LMWH during pregnancy can be expected. There was a trend towards a higher risk of preeclampsia, and these women should be carefully monitored for this complication.     

Serum leptin level in women with idiopathic intracranial hypertension

Leptin is a protein secreted by adipose cells which influences regulation of energy balance and body weight. Idiopathic intracranial hypertension (IIH) is recognised as a neurological disorder mainly affecting obese females. The aim of this study was to evaluate the association between IIH and serum leptin level in 15 obese patients and compare the results with those for 16 obese and 15 non-obese women. A significantly higher serum leptin level was found in patients with IIH than in controls (p<0.0001), and this did not correlate with body mass index (BMI). Serum leptin levels were significantly associated with BMI in both control groups (p<0.0006). Additional factors must therefore be involved in the phenomenon of serum leptin increase beyond weight gain. The cause can only be hypothesised, but it seems that the origin is central, probably hypothalamic.     

Thrombin generation in patients with idiopathic sudden sensorineural hearing loss

Introduction

The pathogenesis of idiopathic sudden sensorineural hearing loss (ISSNHL) is still unknown. Systemic hemostasis derangement causing local vascular occlusion might be one of the pathogenetic mechanisms.

Material and Methods

Forty-one patients with ISSNHL and 48 healthy subjects were investigated. We measured thrombin generation in the presence or absence of thrombomodulin in platelet-poor or platelet-rich plasma by means of a home-made method based on calibrated automated thrombin generation, which should mimic much more closely than any other conventional coagulation test the balance of coagulation operating in vivo. DNA analyses for the most common prothrombotic genotypes such as factor V Leiden, prothrombin G20210A, MTHFR or platelet GPIIIa A1/A2 were also carried out in patients and controls.

Results

Patients generated as much thrombin as controls both in platelet-rich and platelet-poor plasma and the frequency of the most common prothrombotic genotypes were similar in patients and controls.

Conclusions

The results suggest that the pathogenesis of ISSNHL is not due to systemic blood hypercoagulability. Other culprits such as local vascular abnormalities, viral infections, immune-mediated mechanisms or abnormalities of inner ear and central nervous system should be advocated to explain ISSNHL.     

Predictors of seizures during pregnancy in women with epilepsy

We aimed to characterize the seizure pattern during pregnancy in a large cohort of women with epilepsy (WWE) and identify possible predictors of seizure relapse during pregnancy. We recorded the antiepileptic drug (AED) use and seizure frequency for WWE during the prepregnancy month and pregnancy. The seizure profile was correlated with the clinical details and seizure type as abstracted from the clinical records maintained in the registry. Of the 1,297 pregnancies in WWE with complete seizure data, 47.8% were seizure-free during pregnancy. Seizure relapse was highest during the three peripartum days. Women with partial seizures-had higher risk of relapse (odds ratio [OR] 1.6, 95% confidence interval [CI] 1.2-2.0) than those with generalized seizures. They had two peaks of seizure relapse (second to third month and sixth month). Those with generalized seizures had one peak at first trimester. Those who were on polytherapy had increased risk of seizures (OR 2.98, 95% CI 2.3-3.9) when compared to those on monotherapy. Those who had seizures in the prepregnancy month had higher risk (OR 15, 95% CI 9-25.1) of seizures during pregnancy when compared to those who were seizure-free during that period. On multiple logistic regression, prepregnancy seizure was the most important predictor of seizures during pregnancy.     

Sensitivity of the ProC global assay for protein C pathway abnormalities. clinical experience in 899 unselected patients with venous thromboembolism.

The ProC Global is a clotting assay designed to globally evaluate the functionality of the protein C (PC) pathway, which is found defective in up to 30% of the Caucasian patients with thrombophilia. It is based on the ability of endogenous activated protein C (APC), generated by activation of PC by a snake venom extract, to prolong an activated partial thromboplastin time (APTT). This retrospective study was carried out to evaluate the ability of this assay to distinguish patients with or without any PC pathway abnormalities in a cohort of 899 unselected patients with a history of thrombosis. The result of the ProC Global assay, expressed in PC activation time-normalized ratio (PCAT-NR), was significantly lower in patients in whom was previously demonstrated an abnormality of the PC pathway compared to those without. The cut-off level of PCAT-NR=0.75 was found to provide the best sensitivity-specificity ratio, since all the patients with the factor V (FV) Leiden mutation (n=71), APC resistance (n=3), PC deficiency (n=22), or combined defects (n=19) had a PCAT-NR below that value. The sensitivity of the ProC Global assay for a low protein S (PS) level (n=56) was only 66%, and was even weaker in the case of hereditary PS deficiency (46.6%, n=15). The assay did not perform well in samples from patients on oral anticoagulant treatment (OAT, n=64) or with liver failure (n=4), as the PCAT-NR was reduced in most cases, even in the absence of any abnormality. These results suggest that the ProC Global assay could be validly used as a first-step screening test for the FV Leiden-related APC resistance and PC deficiency in patients not on OAT. Given the moderate sensitivity of the assay for PS deficiency, this coagulation inhibitor must be determined in every case. However, the overall benefit of such a screening strategy is limited since more than 38% of the 659 patients without abnormality had a decreased PCAT-NR.     

The effects of benzodiazepines on hormones in women with idiopathic hirsutism

A single blind study was planned to investigate whether benzodiapines would reduce androgens in women with idiopathic hirsutism. Placebo was given for the first month followed by four months of a benzodiazepine (chlorazepate 15 mg nocte or diazepam 10 mg nocte ). Plasma samples were collected during the follicular and luteal phases of each therapy month. Hair growth was assessed monthly. Eighteen women concluded the five months of the trial of whom ten received chlorazepate and eight diazepam. Comparison of follicular plasma samples during the placebo phase and fourth month of benzodiazepine found a significant increase in sex hormone binding globulin and a significant decrease in dehydroepiandrosterone sulphate with benzodiazepine therapy. No significant effects on hair growth were observed. A longer therapy time may be needed to demonstrate effects of benzodiapines on hirsutism. Further studies are needed to determine whether benzodiazepines affect hormonal parameters in normal men and women.     

Protein Z in normal pregnancy

Changes in the coagulation and fibrinolytic systems during pregnancy lead to a higher risk of thromboembolism. These changes include the increase of many clotting factors, as well as a significant fall in activity of fibrinolytic proteins, such as protein C. Protein Z is a vitamin-K-dependent plasma glycoprotein and inhibits the activation of factor X by serving as a cofactor to a plasma proteinase inhibitor. Protein Z deficiency has recently been reported in women with unexplained early fetal losses, and antibodies to protein Z can contribute to adverse pregnancy outcomes. The aim of this study was to determine the range of protein Z in normal pregnancies at different gestational weeks in a cross-sectional and a longitudinal setting. In the longitudinal study we found a 20% increase (p=0.006) of protein Z from first trimester to delivery and a 30% decrease (p<0.0001) 6 to 12 weeks after delivery. In the cross-sectional study these findings were reproducible. In summary, our data show a progressive increase in protein Z levels with gestational age in normal pregnancies and a return to normal levels around 6 to 12 weeks postpartum. The normal increase of protein Z during pregnancy may balance the increase of clotting factors to protect pregnant women from thrombosis.