Heparin or aspirin or both in the treatment of recurrent abortions in women with antiphospholipid antibody (syndrome)

Antiphospholipid Syndrome in Pregnancy: New and Old Pathogenetic Mechanisms

The antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized, according to the Sydney criteria, by the persistent presence of autoantibodies directed against phospholipid-binding proteins associated with thrombosis and/or obstetrical complications. The most frequent complications in obstetric antiphospholipid syndrome are recurrent pregnancy losses and premature birth due to placental insufficiency or severe preeclampsia. In recent years, vascular APS (VAPS) and obstetric APS (OAPS) have been described as two different clinical entities. In VAPS, antiphospholipid antibodies (aPL) interfere with the mechanisms of coagulation cascade and the 'two hit hypothesis' has been suggested to explain why aPL positivity does not always lead to thrombosis. OAPS seems to involve additional mechanisms, such as the direct action of anti-β2 glycoprotein-I on trophoblast cells that can lead to a direct placental functional damage. Furthermore, new actors seem to play a role in the pathogenesis of OAPS, including extracellular vesicles, micro-RNAs and the release of neutrophil extracellular traps. The aim of this review is to investigate the state-of-the-art antiphospholipid syndrome pathogenesis in pregnancy, in order to provide a comprehensive overview of both old and new pathogenetic mechanisms involved in this complex disease.

Off-label indications of aspirin in gynaecology and obstetrics outpatients at two Chinese tertiary care hospitals: a retrospective cross-sectional study

OBJECTIVE

To investigate the prevalence of off-label aspirin indications and the level of scientific support for off-label indications of aspirin in gynaecology and obstetrics outpatients.

DESIGN

A retrospective cross-sectional study.

SETTING

Two tertiary hospitals (a general hospital and a women and children's specialised hospital) in Xiamen, a city located on the southeastern coast of China.

PARTICIPANTS

A total of 4257 prescriptions were included for 2091 female patients aged >18 who visited the gynaecology and obstetrics outpatient clinics and received aspirin treatment.

OUTCOME MEASURES

The primary measure of this study was the proportion of off-label indications and of off-label indications supported by strong scientific evidence. Evidence from clinical guidelines and Micromedex is shown using descriptive statements. On-label indications of drugs in the same class as aspirin were also referred to for off-label aspirin use without strong evidence support.

RESULTS

All indications of aspirin on outpatient prescriptions were determined as off-label use in this study. The most frequent off-label indication was recurrent miscarriage (2244 prescriptions, 52.71%). Totally, 30.94% of the prescriptions were supported by strong evidence for indications, including recurrent miscarriage with antiphospholipid syndrome and prophylaxis for pre-eclampsia. No drugs in the same class as aspirin had on-label indications for off-label aspirin use without strong evidence support.

CONCLUSIONS

This study demonstrated that all indications of aspirin used in gynaecology and obstetrics outpatients at the two tertiary hospitals were off-label and not always supported by strong evidence, implicating that physicians should be cautious when issuing off-label prescriptions. More original clinical research on off-label aspirin use is needed to provide reference for routine clinical practice.

In silico identification of new inhibitors for βeta-2-glycoprotein I as a major antigen in antiphospholipid antibody syndrome

Beta 2 glycoprotein I (β2GPI) is a major antigen for autoantibodies present in antiphospholipid antibody syndrome (APS). β2GPI is a single polypeptide with five repeated domains and different conformations. The activated J-shaped conformation of β2GPI binds to negatively charged phospholipids in the membrane via the fifth domain and causes blood clotting reactions. We applied a drug repurposing strategy using virtual screening and molecular dynamics to find the best FDA drugs against the fifth domain of β2GPI. In the first phase, FDA drugs that had the most favorable ΔG with the fifth domain of β2GPI were selected by virtual screening. Among these drugs that had the most favorable ΔG, Vorapaxar and Antrafenine were selected for molecular dynamics (MD) simulation studies. MD simulation was performed to evaluate the stability of Vorapaxar and Antrafenine complexes and the effect of the two drugs on protein conformation. Also, MD simulation was done to investigate the effect of Antrafenine and Vorapaxar on the binding of β2GPI to the platelet model membrane. According to the results, Vorapaxar and Antrafenine were bound to the protein with the favorable binding energy (Vorapaxar and Antrafenine binding energies are - 49.641 and - 38.803 kcal/mol, respectively). In this study, it was shown that unlike protein alone and protein in the Antrafenine complex, the protein in the Vorapaxar complex was completely separated from the model membrane after 350 ns. Moreover, Vorapaxar led to more changes in the activated J-shape of β2GPI. Thus, Vorapaxar can be a suitable candidate for further investigations on the treatment of APS.

Paternal HLA-C is a risk factor in unexplained recurrent miscarriage

PROBLEM

HLA-C is the only classical HLA-I antigen expressed on trophoblast. We hypothesized that the alloimmune response to paternal HLA-C plays a role in unexplained recurrent miscarriage.

METHOD OF STUDY

In a case-control design, we included 100 women with at least three unexplained consecutive miscarriages along with their partners and children. For the first control group, we included 90 women with an uneventful singleton pregnancy without pregnancy complications in their history along with their children. The second control group consisted of 425 families. HLA-C*07 and HLA-C*17 frequencies, which are the most immunogenic HLA-C antigens, along with HLA-C mismatches, and the presence of specific HLA antibodies in the mother were determined.

RESULTS

HLA-C and HLA-C*07 mismatches were significantly increased in couples with recurrent miscarriage compared to control subjects (P = .016, P = .008, respectively). The incidence of child-specific HLA-C*07/HLA-C*17 antibodies was increased in women with recurrent miscarriage (P = .007).

CONCLUSION

The results show that HLA-C incompatibility between couples is significantly associated with unexplained recurrent miscarriage.

Thromboprophylaxis and maternal-fetal outcomes of women with serum markers for hereditary thrombophilia and previous obstetric complications

Abstract Objectives: to evaluate the maternalfetal outcomes of thromboprophylaxis with enoxa parin based on scoring system in women with serum markers for hereditary thrombophilia and previous obstetric complications. Methods: a retrospective study was undertaken based on data collected from clinical records. We included 54 pregnant women with serum markers for hereditary thrombophilia undergoing therapeutic intervention with enoxaparin in the period from November 2009 to December 2013. The initial dose of low molecular weight heparin was guided by a scoring system. The maternalfetal outcomes of previous pregnancies and, subsequently, the treatment were compared using the chisquare (χ2) test with the Yates correction and Fisher's Exact Test; p<0.05 was considered significant. Results: we observed significant reduction in fetal/perinatal deaths (p<0.05) and spontaneous abortions (p<0.001) after intervention. The live births at fullterm delivery (p<0.001) and live births at preterm delivery (p<0.05) increased significantly after intervention. Conclusions: the therapeutic intervention with enoxaparin based on scoring system during pregnancy seems to improve the fetal prognosis.

Recurrent pregnancy loss: current perspectives

Recurrent pregnancy loss is an important reproductive health issue, affecting 2%–5% of couples. Common established causes include uterine anomalies, antiphospholipid syndrome, hormonal and metabolic disorders, and cytogenetic abnormalities. Other etiologies have been proposed but are still considered controversial, such as chronic endometritis, inherited thrombophilias, luteal phase deficiency, and high sperm DNA fragmentation levels. Over the years, evidence-based treatments such as surgical correction of uterine anomalies or aspirin and heparin for antiphospholipid syndrome have improved the outcomes for couples with recurrent pregnancy loss. However, almost half of the cases remain unexplained and are empirically treated using progesterone supplementation, anticoagulation, and/or immunomodulatory treatments. Regardless of the cause, the long-term prognosis of couples with recurrent pregnancy loss is good, and most eventually achieve a healthy live birth. However, multiple pregnancy losses can have a significant psychological toll on affected couples, and many efforts are being made to improve treatments and decrease the time needed to achieve a successful pregnancy. This article reviews the established and controversial etiologies, and the recommended therapeutic strategies, with a special focus on unexplained recurrent pregnancy losses and the empiric treatments used nowadays. It also discusses the current role of preimplantation genetic testing in the management of recurrent pregnancy loss.

Obstetric antiphospholipid syndrome: a recent classification for an old defined disorder

Obstetric antiphospholipid syndrome (APS) is now being recognized as a distinct entity from vascular APS. Pregnancy morbidity includes >3 consecutive and spontaneous early miscarriages before 10weeks of gestation; at least one unexplained fetal death after the 10th week of gestation of a morphologically normal fetus; a premature birth before the 34th week of gestation of a normal neonate due to eclampsia or severe pre-eclampsia or placental insufficiency. It is not well understood how antiphospholipid antibodies (aPLs), beyond their diagnostic and prognostic role, contribute to pregnancy manifestations. Indeed aPL-mediated thrombotic events cannot explain the obstetric manifestations and additional pathogenic mechanisms, such as a placental aPL mediated complement activation and a direct effect of aPLs on placental development, have been reported. Still debated is the possible association between aPLs and infertility and the effect of maternal autoantibodies on non-vascular manifestations in the babies. Combination of low dose aspirin and unfractionated or low molecular weight heparin is the effective treatment in most of the cases. However, pregnancy complications, in spite of this therapy, can occur in up to 20% of the patients. Novel alternative therapies able to abrogate the aPL pathogenic action either by interfering with aPL binding at the placental level or by inhibiting the aPL-mediated detrimental effect are under active investigation.

Study on the pathogenesis of autoimmune-type recurrent spontaneous abortion by establishing a new mouse model

OBJECTIVE

To establish a new mouse model for autoimmune-type recurrent spontaneous abortion (AI-RSA) and demonstrate the potential role of intrauterine immunization with β2GP-1-like antigen in AI-RSA, we performed an intrauterine injection of human β2GP-1 in BALB/c mice and unrelated protein, adjuvants, and normal saline (NS) as controls. The mean number of embryos implanted (MNEI), embryo loss rate (ELR), mean embryo bulk (MEB), and mean placental weight (MPW) were analyzed. Compared with the control mice, BALB/c mice injected with human β2GP-1 showed increased anti-β2GP-1 and MPW. Moreover, BALB/c mice immunized with human β2GP-1 exhibited hypercoagulability and vascular thrombus formation in the placenta. Electron microscopy confirmed the existence of platelet aggregation, mitochondrial swelling, and endothelial cell necrosis in the placentas of BALB/c mice immunized with human β2GP-1. These finding indicated that intrauterine immunization with β2GP-1 successfully induced AI-RSA in mice. Increased anti-β2GP-1 antibody could independently induce hypercoagulability, vascular endothelial injury, and vascular thrombus formation in the placenta, which led to AI-RSA.

Coagulation and the fibrin network in rheumatic disease: a role beyond haemostasis

Activation of the immune system has been increasingly recognised to be associated with procoagulatory status in patients with inflammatory rheumatic disease. Changes in endothelial cell and platelet activation, blood flow, expression and activity of different coagulation factors, and impaired fibrinolysis serve as pathophysiological basis for enhanced risk of venous thromboembolism in inflammatory rheumatic diseases, such as rheumatoid arthritis (RA), connective tissue diseases and vasculitides. Recent studies identifying mechanisms for a functional role of coagulation factors beyond haemostasis have provided examples of interesting links between the coagulation system and innate immune activation. Furthermore, citrullinated fibrinogen is an important and early autoantigen in patients with RA carrying the HLA-DRβ1 shared epitope allele, which demonstrates an adaptive immune response to a coagulation factor in an inflammatory rheumatic disease. Additional studies have provided strong evidence that a multitude of different components of the haemostatic system (such as thrombin, fibrinogen, coagulation factor XIII and factors of the fibrinolytic system) are relevant mediators of inflammatory processes as well as of inflammatory control. Understanding the interactions between coagulation and the immune system in inflammatory rheumatic diseases will not only improve our knowledge of disease mechanisms, but could also permit the development of innovative therapeutic interventions.

Recurrent miscarriage and thrombophilia: an update

PURPOSE OF REVIEW

Acquired and inherited thrombophilia is an important research avenue in the recurrent miscarriage field. The optimum treatment for patients with recurrent miscarriage and a confirmed thrombophilia remains a contentious issue. We aim to appraise and explore the latest research in the field of thrombophilia and recurrent miscarriage in this review.

RECENT FINDINGS

Antiphospholipid syndrome (APS) is the only proven thrombophilia that is associated with adverse pregnancy outcomes. Research involving inherited thrombophilia and recurrent miscarriage is limited to small observational studies with small and heterogeneous populations. Aspirin and heparin therapy are frequently prescribed for APS, yet there is no robust evidence for the most efficacious regime. The combination of inherited hypercoagulability and environmental factors in association with recurrent miscarriage has recently been explored as an aid to identify high-risk individuals.

SUMMARY

The cause of recurrent miscarriage is multifactorial and appropriate treatment continues to be a challenge. Laboratory tests need to be standardized and well designed multicentre research trials are essential to expand on the current knowledge base with the aim to produce strong evidence-based medicine.

Caring for reproductive-aged women with spinal cord injuries: a case report

In 2008 there were an estimated 259,000 people living in the USA with spinal cord injuries (SCI). The majority of these people are in their reproductive years, and over 19% are estimated to be women. Advances in medical management have allowed many women to live successfully with congenital defects or injuries resulting in SCI that even a few years ago would have been fatal. Although many of these women may be classified as 'disabled', fertility is not usually affected in SCI and many of these women desire children of their own. It is important to counsel these women regarding the range of issues related to pregnancy. These include conception issues, parenting with a disability, emotional concerns of the family, nutrition and exercise in pregnancy, risks in pregnancy, labour and delivery, postpartum care, and breastfeeding. For health-care providers it is important to know and understand your patient's disability and be able to provide the best patient-centred quality care, understanding that each patient's circumstance may be unlike any other patient.

Anti-phospholipid induced murine fetal loss: novel protective effect of a peptide targeting the β2 glycoprotein I phospholipid-binding site. Implications for human fetal loss

β2 glycoprotein I (β2GPI)-dependent anti-phospholipid antibodies (aPL) induce thrombosis and affect pregnancy. The CMV-derived synthetic peptide TIFI mimics the PL-binding site of β2GPI and inhibits β2GPI cell-binding in vitro and aPL-mediated thrombosis in vivo. Here we investigated the effect of TIFI on aPL-induced fetal loss in mice. TIFI inhibitory effect on in vitro aPL binding to human trophoblasts was evaluated by indirect immunofluorescence and ELISA. TIFI effect on aPL-induced fetal loss was investigated in pregnant C57BL/6 mice treated with aPL or normal IgG (NHS). Placenta/fetus weight and histology and RNA expression were analyzed. TIFI, but not the control peptide VITT, displayed a dose-dependent inhibition of aPL binding to trophoblasts in vitro. Injection of low doses of aPL at day 0 of pregnancy caused growth retardation and increased fetal loss rate, both significantly reduced by TIFI but not VITT. Consistent with observations in humans, histological analysis showed no evidence of inflammation in this model, as confirmed by the absence of an inflammatory signature in gene expression analysis, which in turn revealed a TIFI-dependent modulation of molecules involved in differentiation and development processes. These findings support the non-inflammatory pathogenic role of aPL and suggest innovative therapeutic approaches to aPL-dependent fetal loss.

Hydroxychloroquine reduces binding of antiphospholipid antibodies to syncytiotrophoblasts and restores annexin A5 expression

OBJECTIVE

Antibody-mediated disruption of the annexin A5 anticoagulant shield has been posited to be a thrombogenic mechanism in the antiphospholipid syndrome. We recently showed that the antimalarial drug, hydroxychloroquine, dissociates antiphospholipid immune complexes and restores annexin A5 binding to planar phospholipid bilayer. Using quantitative immunoassays, we demonstrated similar effects on BeWo trophoblasts. We therefore, investigated the effects of the drug on localization of annexin A5 in primary cultures of human placental syncytiotrophoblasts.

STUDY DESIGN

Laser confocal microscopy with computer-based morphometric analysis was used to localize annexin A5 and antiphospholipid antibodies on syncytiotrophoblasts exposed to polyclonal and monoclonal antiphospholipid and control immunoglobulin-Gs.

RESULTS

Hydroxychloroquine reversed the effects of the antiphospholipid antibodies on the syncytiotrophoblasts by markedly reducing immunoglobulin-G binding and restoring annexin A5 expression.

CONCLUSION

These results provide the first morphologic evidence for this effect of hydroxychloroquine on human placental syncytiotrophoblasts and support the possibility of novel treatments that target antiphospholipid antibody binding.

Uso de la heparina de bajo peso molecular y aspirina en una paciente con síndrome antifosfolípido y pérdida gestacional recurrente

Introducción: La pérdida gestacional recurrente (PGR) es una patología frecuente, que causa gran impacto en las parejas conllevando frustración, ansiedad, depresión, gastos excesivos y hasta rupturas de la relación de pareja. Su etiología es multicausal  y frecuentemente no se logra determinar. Se presenta el caso de una paciente con PGR quien luego de seis pérdidas gestacionales, en el séptimo embarazo se detectaron anticuerpos antifosfolípidos altos, recibiendo tratamiento de tromboprofilaxis doble hasta la semana 32, obteniéndose un producto pretérmino vivo y sano  que  evolucionó  satisfactoriamente.  Se  discuten dificultades para la precisión diagnóstica y las modalidades de tratamiento descritos.