Sonal Vora

Contribution of natural anticoagulant and fibrinolytic factors in modulating the clinical severity of haemophilia patients

The role of natural anticoagulants, fibrinolytic cascade factors and common prothrombotic gene polymorphisms in modulating disease severity were studied in 35 ‘clinically mild’ and 37 ‘clinically severe’ haemophilia patients with severe factor VIII or IX deficiency (<0·01 IU/ml). Strong association of deficiencies of proteins C and S, antithrombin III, tissue factor pathway inhibitor and tissue plasminogen activator, together with factor V Leiden and endothelial protein C receptor 23 bp insertion polymorphisms were observed in the ‘clinically milder’ group as compared with the ‘clinically severe’ group. These results indicate a synergistic modulation of bleeding tendency in haemophilia patients by factors in the anticoagulant and fibrinolytic systems.

Deep venous thrombosis in the antenatal period in a large cohort of pregnancies from western India

BackgroundDeep venous thrombosis (DVT) is an important complication in the peripartal and postpartal period.MethodsWe followed up prospectively the prevalence of DVT in 34720 prenatal mothers between June 2002 and July 2006 attending the antenatal clinics of two major hospitals in Mumbai, India. Thirty two women (0.1%) presented for the first time with symptomatic DVT i.e. 17 in the first trimester, 6 in the second and 9 in the third trimester of pregnancy. Nine had history of fetal loss while in the remaining twenty three there was no history of fetal loss.ResultsThe evaluation of both acquired and heritable thrombophilia showed a conglomeration of thrombophilia in this group when compared to 100 normal pregnant women who have given birth to at least one healthy baby with no history of fetal death, DVT or other obstetrical complications. The relative risks for all the antiphospholipid antibodies (APA) studied i.e lupus anticoagulant (LA), IgG/IgM antibodies for cardiolipin (ACA), β2 glycoprotein 1 (β2 GP 1) and annexin V were significantly higher in women with pregnancy associated DVT (RR 7.4 95% CI 4.3–11.3 P < 0.05). Among the genetic thrombophilia markers studied, Protein S (PS) deficiency was the strongest risk factor (RR 5.00 95% CI 3.02–5.00 P < 0.05) followed by factor V Leiden (FVL) mutation (RR 4.57 95% CI 2.23–4.57 P < 0.05) and PAI 4G/4G homozygosity (RR 3.24 95% CI 1.85–5.12 P < 0.05). Protein C (PC) and endothelial protein C receptor (EPCR) 23 bp insertion polymorphism was also increased in the patient group as compared to controls but the difference was not statistically significant. The MTHFR C677T, fibrinogen gene β448 Arg/Lys polymorphisms were not significantly different from the normal controls, while antithrombin III (AT III) deficiency and PT G20210A polymorphism were absent in both controls and patients. Two or more risk factors were present in 22 out of 32 cases (68.75%).ConclusionWe conclude that the prevalence of DVT in India is more or less similar to other reports published and both acquired and heritable thrombophilia show strong association with DVT associated with pregnancy.

Thrombophilic dimension of recurrent fetal loss in Indian patients.

We studied the prevalence of acquired and genetic thrombophilia in 198 women with recurrent fetal loss who were having three or more than three abortions. Seventy-nine women had only early pregnancy losses, that is, first trimester abortions, 30 women had only late pregnancy losses, that is, second and third trimester abortions whereas 89 had both early and late pregnancy losses. The control group included 100 age-matched fertile parous women who did not have any obstetric complications and had at least one normal healthy child. Several genetic and acquired thrombophilia markers were studied. The strongest association was observed with anticardiolipin (odds ratio 22.6, confidence interval 5.7–89, P = 0) followed by lupus anticoagulant, anti-β2 glycoprotein-1, antiannexin. Association of antiphospholipid antibody syndromes was detected with the time of pregnancy loss in anticardiolipin, lupus anticoagulants, which was significantly associated with early pregnancy loss as compared with second and third trimester loss. In case of β2 glycoprotein-1, antiannexin it was less significantly associated with early pregnancy loss as compared with second and third trimester loss. The risk of fetal loss with protein S deficiency was the highest risk observed for any heritable thrombophilia, followed by protein C, factor V Leiden, endothelial protein C receptor, antithrombin III deficiency and β448 fibrinogen polymorphism. Modest risks were also observed with 5,10-methylenetetrahydrofolate reductase, plasminogen activator inhibitor 4G/4G polymorphisms and β448 fibrinogen polymorphism. A combination of two or more than two genetic risk factors were observed in 55 (27.7%), whereas the genetic and acquired risk factors were observed in 107 (54%) of the cases. Thrombophilia is an important contributing factor for both early and late pregnancy losses; approximately two-thirds of our cases of unexplained fetal losses could be explained by acquired or heritable thrombophilia or both, which is in line with other western studies.

Successful Pregnancy Outcome in Women With Bad Obstetric History and Recurrent Fetal Loss Due to Thrombophilia: Effect of Unfractionated Heparin and Low—Molecular Weight Heparin:

Acquired and inherited thrombophilias are known to be associated with unfavorable pregnancy outcome including recurrent fetal loss. There are differences of opinion whether these patients need to be treated with aspirin, unfractionated heparin, low—molecular weight heparin, corticosteroids, or intravenous immunoglobulins. In all, 25 consecutive patients with a history of fetal loss and 7 patients who presented in early pregnancy with deep-vein thrombosis were treated, and their pregnancy outcome was noted. All the women were positive either for a solitary or for a combination of acquired and heritable thrombophilia markers. In all, 23 patients were treated with unfractionated heparin and 9 with low—molecular weight heparin. In all, 16 out of 23 patients (69.6%) treated with unfractionated heparin and 9 out of 9 (100%) treated with low—molecular weight heparin had successful pregnancy outcome. There was a complete resolution of thrombus in all the cases. None of the patients had any adverse reactions such as heparin-induced thrombocytopenia, thrombosis, or fracture. Both unfractionated heparin and low—molecular weight heparin were effective in cases of bad obstetric history and recurrent pregnancy loss due to thrombophilia. However, low—molecular weight heparin was found to be more effective than unfractionated heparin along with other advantages of not requiring laboratory monitoring and easy administration. None of the patients in either group had to interrupt the therapy for any adverse treatment-related complications.

Inherited and acquired thrombophilia in Indian women experiencing unexplained recurrent pregnancy loss

The most frequently hypothesized cause of unexplained recurrent pregnancy loss (RPL) refers to a defective maternal haemostatic response leading to uteroplacental thrombosis. Approximately 20% women suffering from pregnancy loss (PL) are associated with autoimmune disorders and more than 50% remain idiopathic after common traditional investigations. The present study aims to investigate the prevalence of different genetic and acquired thrombophilia markers in a large series of Indian women with RPL. Such studies will help analyze the markers which pose maximum risk and help in the appropriate treatment in subsequent pregnancies. The study comprised of 587 women with no apparent etiological causes of RPL and 115 healthy women controls. p values were calculated with two tailed Fishers exact test; statistical significance was assumed at p<0.05, 95% confidence interval. Relative risks were also calculated. Among genetic thrombophilia, the risk of PL was highest with protein S deficiency (16%, p=0.006) followed by plasminogen activator inhibitor-1 4G/4G (23%, p=0.007) polymorphism. Among acquired markers, the risk of PL was the highest in women with anti-cardiolipin antibodies (24%, p=0.0001), followed by anti-annexin V antibodies (23%, p=0.0009) and lupus anticoagulants (8%, p=0.02). Thrombophilia, inherited and acquired, is an important contributing factor in unexplained RPL and should be screened in the order of its prevalence.

Plasminogen activator inhibitor-1 4G/5G gene polymorphism in women with fetal loss

A dramatic change in most of the coagulation factors and natural inhibitors of coagulation occurs in healthy pregnancy to enable the body to reduce hemorrhage during child birth. Stabilization of blood clotting is also brought about by inhibition of fibrinolysis. Several plasminogen activator inhibitors (PAIs) inhibit fibrinolysis by interfering with plasminogen activation; the most important of these is PAI-1. During pregnancy the placenta produces PAI-1, which may maintain hemostasis during pregnancy at the placental bed, but is not available after delivery to prevent postpartum blood loss. The common PAI-1 polymorphism, PAI 4G/4G, is associated with higher levels of PAI-1 in the plasma and thrombosis in various thromboembolic conditions [1]. A recent meta-analysis of 22 studies showed a significant association between this polymorphism and venous thromboembolism, particularly in patients with a second genetic risk factor [2]. During pregnancy, the volume of blood flowing through the placental bed is significant and contributes approximately 20% of the total cardiac output (700–800 mL per minute). The increased flow of blood is needed to nourish the growing fetus, facilitate the exchange of oxygen and carbon dioxide, and removewaste products. If there is a reduction in placental circulation due to vascular occlusion, fetal growth is compromised, which may lead to intrauterine fetal death or other adverse conditions. Thrombophilia may be useful in pregnancy to stop postpartum bleeding. Evolution through natural selection has allowed the conglomeration of thrombophilic genes to prevent death from hemorrhage, but when overexpressed they can cause recurrent fetal loss [3]. The present study assessed PAI-1 4G/5G polymorphism in 430 consecutive women with a history of unexplained fetal loss and 32 women with deep vein thrombosis (DVT) associated with pregnancy with or without a history of fetal loss, after ruling out the conventional causes. Inclusion criteria were normal findings for the following: karyotype of both parents, toxoplasmosis serology, liver function tests, anatomical abnormalities, intrauterine adhesion and cervical incompetence, thyroid function, serum prolactin levels, and plasma progesterone levels. The study participants were compared with 100 healthy pregnant women with no previous history of spontaneous abortion or pregnancy-related complications who had at least one healthy baby at the time of the study. Informed consent was ob-

Antiphospholipid antibodies in haemophilia patients with severe bleeding tendency: cause, consequence or a consequential cause?

Summary.  The prevalence, cause and the impact of antiphospholipid antibodies (APAs) on the clinical severity in haemophilia patients is poorly studied. We studied 72 severe seronegative (negative for HIV, HBsAg, HCV) haemophilia patients for the presence of four common APAs. Twenty‐six (36.1%) were positive for any one of the APAs studied of which eight were positive only for anticardiolipin antibodies, three for β2 glycoprotein (β2GP1), four for prothrombin (PT) and six for anti annexin antibodies. Remaining six patients showed multi‐specific antibodies. Further, clinically severe haemophilia patients (n = 37) showed higher prevalence of APAs as compared with the clinically milder group (n = 35) suggesting that these antibodies do not contribute in alleviating the clinical severity in haemophilia patients as has been observed with other inherited thrombophilia markers. The study of in vitro thrombin generation showed a higher endogenous thrombin potential (ETP) i.e. almost normal, in case of β2GP1‐positive patients as compared with patients with other types of APAs. High prevalence of APAs in clinically severe haemophilia patients may be a consequence of continuing tissue damage in the clinically severe group; as in India, clotting factor concentrates cannot be used ad lib because of financial constraints. Higher thrombin‐generating potential in case of patients positive for β2GP1 did not seem to have any impact on the clinical severity of haemophilia patients.

Coagulation factor deficiency as a cause of recurrent fetal loss: a red herring!

Whether severe coagulation factor deficiency can cause adverse pregnancy outcomes or recurrent fetal loss is not definitely known. We report here on five women with severe deficiency of coagulation factors (two factor X, one factor XI, one factor VII and one von Willebrand factor) who presented with history of unexplained fetal loss or with adverse pregnancy outcome. Detailed investigations of thrombophilia showed that four patients were positive for antiphospholipid antibodies, one of whom was also homozygous for the plasminogen-activator inhibitor-1 4G/4G polymorphism, and the fifth patient was deficient for protein C. Despite the concomitant presence of both coagulation factor defect and thrombophilia, fetal loss may be attributed to factor defect that in reality is a red herring, with underlying thrombophilia not being evaluated.

Previous fetal loss significantly increases the risk of pre-partal deep-vein thrombosis

We read with interest the report by De Stefano et al (2006) regarding the risk of recurrent venous thromboembolism in pregnancy and puerperium. This comprehensive study showed that prevalence of thrombophilia did not differ significantly in the cohort of pregnant women with or without deep-vein thrombosis (DVT) and the presence of a provoking factor for previous DVT did not increase the risk for DVT in subsequent pregnancies. Between 2002 and 2006, we studied all the pregnancyrelated DVT cases that presented at two of the busiest hospitals in Mumbai. Out of 25 132 multigravida women examined, 32 had DVT during their current pregnancy, based on the clinical features that were confirmed by Doppler studies. Clinically inapparent cases (absence of oedema, redness, pain and calf tenderness) were not investigated for subclinical DVT. Nine out of 462 women with previous history of fetal loss had DVT whereas 23 out of 24 670 with no history of previous fetal loss and no other precipitating risk factor, such as toxaemia, dehydration or smoking, had a pregnancy-related DVT in the current pregnancy. Hence, the risk of clinically apparent DVT during pregnancy was 22fold higher if there was a previous history of one or more pregnancy loss (chi-squared test P <0 AE001). Laboratory investigations for thrombophilia, i.e. lupus antibodies, IgG/