Síndrome antifosfolipídico obstétrico

Optical coherence tomography angiography evaluation of retinal and choroidal microvascular changes in pregnant women with a history of unexplained recurrent spontaneous abortions

PURPOSE

To study retinal and choroidal microcirculation by optical coherence tomography angiography (OCTA) in pregnant women with unexplained recurrent spontaneous abortion (RSA) and to compare them with healthy pregnant and nonpregnant subjects.

METHODS

Pregnant women with an unexplained history of RSA (group 1), healthy pregnant (group 2), and healthy non-pregnant women (group 3) were included in the study. After a thorough ophthalmologic examination:best-corrected visual acuity, intraocular pressure,slit-lamp biomicroscopy, fundus examination,autorefractometer, biometry, and axial length measurement; OCT and OCTA measurements were performed with Swept Source OCT-Angiography (Topcon Co, Japan).

RESULTS

The nonpregnant group had higher values for central foveal superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density (VD) and lower values for superior, inferior, and mean VD compared with pregnant groups (p < 0.001). Choriocapillaris values (CC) VD were higher in groups 1 and 2 than in group 3 (p < 0.001). The group with unexplained RSA had a relatively smaller FAZ (foveal avascular zone) area than the group of healthy pregnant women (p:0.047). There were no statistically significant differences between groups in the retina, retinal nerve fiber layer, ganglion cell layer, and choroidal thickness (p > 0.05).

CONCLUSION

Although our study did not identify any etiology in pregnant women with RSA, we observed detectable differences in FAZ area and vessel density values using OCTA, when comparing them with healthy pregnant women and healthy nonpregnant controls. We believe that OCTA, as used in many pathologies such as diabetic and hypertensive retinopathy and retinal vascular occlusion, can also be extended to unexplained RSA both to detect etiology and to monitor treatment in studies with a larger number of patients.

Preeclampsia and the Antiphospholipid Syndrome

Antiphospholipid syndrome (APS) is characterized by venous or arterial thrombosis and/or adverse pregnancy outcome in the presence of persistent laboratory evidence of antiphospholipid antibodies (aPLs). Preeclampsia complicates about 10-17% of pregnancies with APS. However, only early onset preeclampsia (<34 weeks of gestation) belongs to the clinical criteria of APS. The similarities in the pathophysiology of early onset preeclampsia and APS emphasize an association of these two syndromes. Overall, both are the result of a defective trophoblast invasion and decidual transformation at early gestation. Women with APS are at increased risk for prematurity; the reasons are mostly iatrogenic due to placental dysfunction, such as preeclampsia or FGR. Interestingly, women with APS have also an increased risk for preterm delivery, even in the absence of FGR and preeclampsia, and therefore it is not indicated but spontaneous. The basic treatment of APS in pregnancy is low-dose aspirin and low-molecular-weight heparin. Nevertheless, up to 20-30% of women develop complications at early and late gestation, despite basic treatment. Several additional treatment options have been proposed, with hydroxychloroquine (HCQ) being one of the most efficient. Additionally, nutritional interventions, such as intake of vitamin D, have shown promising beneficial effects. Curcumin, due to its antioxidant and anti-inflammatory properties, might be considered as an additional intervention as well.

Contradictory Effect of Lymphocyte Therapy and Prednisolone Therapy on CD3+CD8+CD56+ Natural Killer T Population in Women with Recurrent Spontaneous Abortion

Background

Natural killer T (NKT) cells are influential immune cells in pregnancy failures, including recurrent spontaneous abortion (RSA). Different approaches are used for these disorders due to their effects on maternal immunomodulation.

Aims

In the present study, we compared the effects of two typical immunotherapies (lymphocyte immunotherapy [LIT] and low-dose prednisolone) on CD3+CD56+CD16+ and CD3+CD56+CD8+ cells as two distinct subsets of NKT cells in Women with RSA.

Settings and Design

This study was a comparative cohort study conducted from 2021 to 2022. One hundred and five women with RSA were distributed into three treatment groups randomly.

Materials and Methods

Fifty women in the group of low-dose prednisolone therapy, fifty women in the LIT group and five women without any treatment as the control group were included in the study. NK and NKT cell subsets were assessed using flow cytometry. Furthermore, the concentration of interferon-gamma (IFN-γ), transforming growth factor-beta (TGF-β) and interleukin-10 (IL-10) was measured quantitatively using the enzyme-linked immunosorbent assay technique.

Statistical Analysis Used

Normality and comparisons between study groups were performed by non-parametric unpaired Mann-Whitney, Kruskal-Wallis rank sum test, and one-way ANOVA.

Results

The percentage of CD56dim NK cells was increased after prednisolone therapy, while this population significantly decreased in the LIT group. In contrast to the LIT group, the administration of prednisolone increased CD3+CD8+CD56+ NKT cells (P < 0.0001), which is helpful for pregnancy. The effect of the investigated treatment approaches on the population of peripheral CD3+CD56+CD16+ NKT cells of women with RSA was not adequately significant. The same situation was also observed regarding the serum level of IFN-γ. However, a significant decrease in serum levels of IL-10 and TGF-β was observed after prednisolone therapy.

Conclusion

The lower capability of LIT in changing the population of NKT cells compared to prednisolone therapy may be due to its mechanism of action, which is related to the production of blocking antibodies. These treatment approaches had different effects on NKT cells, indicating that NKT cell population and function can be affected using LIT and prednisolone therapy distinctly. In addition, prednisolone therapy and LIT in women with normal serum levels of IFN-γ have no harmful effects in changing the production of this critical cytokine.

Hemorrhage complications in obstetric antiphospholipid syndrome: Risk factors and association with adverse pregnancy outcomes

Background

Bleeding complications are recognized as relatively infrequent manifestations of antiphospholipid syndrome (APS), and the safety of antithrombotic therapy during pregnancy is of concern. This study aims to assess the risk factors and possible associations between bleeding complications and adverse pregnancy outcomes (APOs) in patients with APS.

Methods

A retrospective cohort study was conducted at the Peking University People’s Hospital. The clinical and immunologic features, bleeding complications, treatment, and pregnancy outcomes of patients with APS were collected. Univariate and multivariate logistic regression analyses were applied to assess the associations between APOs and bleeding complications.

Results

A total of 176 participants with obstetric APS were included in the analysis. There were 66 (37.50%) patients with APS with hemorrhage complications and 86 (48.86%) patients with APS with APOs. Mucocutaneous hemorrhage was associated with APOs including fetal death after 12 weeks [odds ratio (OR) = 10.73, 95% confidence interval (CI): 1.61–71.74, p = 0.014], preterm delivery prior to 34 weeks (OR = 8.30, 95% CI: 2.31–29.84, p = 0.001), and small for gestational age (OR = 4.17, 95% CI: 1.22–14.21, p = 0.023) in univariate logistic regression analyses. It also independently associated with preterm delivery prior to 34 weeks (OR = 40.29, 95% CI: 1.45–1121.32, p = 0.030) in multivariate logistic regression analyses. Receiver operating characteristic (ROC) analysis evaluating the accuracy of these factors for preterm delivery prior to 34 weeks showed that the area under ROC curve was 0.871.

Conclusion

The study shows that mucocutaneous hemorrhage may be an indication of the occurrence of APOs in obstetric patients with APS.

Pathogenesis, Diagnosis and Management of Obstetric Antiphospholipid Syndrome: A Comprehensive Review

Antiphospholipid syndrome is an autoimmune disorder characterized by vascular thrombosis and/or pregnancy morbidity associated with persistent antiphospholipid antibody positivity. Cases fulfilling the Sydney criteria for obstetric morbidity with no previous thrombosis are known as obstetric antiphospholipid syndrome (OAPS). OAPS is the most identified cause of recurrent pregnancy loss and late-pregnancy morbidity related to placental injury. Cases with incomplete clinical or laboratory data are classified as obstetric morbidity APS (OMAPS) and non-criteria OAPS (NC-OAPS), respectively. Inflammatory and thrombotic mechanisms are involved in the pathophysiology of OAPS. Trophoblasts, endothelium, platelets and innate immune cells are key cellular players. Complement activation plays a crucial pathogenic role. Secondary placental thrombosis appears by clot formation in response to tissue factor activation. New risk assessment tools could improve the prediction of obstetric complication recurrences or thromboses. The standard-of-care treatment consists of low-dose aspirin and prophylactic low molecular weight heparin. In refractory cases, the addition of hydroxychloroquine, low-dose prednisone or IVIG improve pregnancy outcomes. Statins and eculizumab are currently being tested for treating selected OAPS women. Finally, we revisited recent insights and concerns about the pathophysiology, diagnosis and management of OAPS.

Antiphospholipid Antibodies From Women With Pregnancy Morbidity and Vascular Thrombosis Induce Endothelial Mitochondrial Dysfunction, mTOR Activation, and Autophagy

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by thrombosis and pregnancy morbidity (PM) obstetric events together with persistent high titers of circulating antiphospholipid antibodies (aPL). Several mechanisms that explain the development of thrombosis and PM in APS include the association of aPL with alterations in the coagulation cascade and inflammatory events. Other mechanisms disturbing cellular homeostases, such as mitochondrial dysfunction, autophagy, and cell proliferation, have been described in other autoimmune diseases. Therefore, the objective of this study was to investigate the impact of aPL from different patient populations on endothelial cell mitochondrial function, activation of the mammalian target of rapamycin (mTOR) and autophagy pathways, and cellular growth. Using an in vitro model, human umbilical vein endothelial cells (HUVECs) were treated with polyclonal immunoglobulin G (IgG) purified from the serum of women with both PM and vascular thrombosis (PM/VT), with VT only (VT), or with PM and non-criteria aPL (seronegative-obstetric APS, SN-OAPS). We included IgG from women with PM without aPL (PM/aPL-) and healthy women with previous uncomplicated pregnancies (normal human serum, NHS) as control groups. Mitochondrial function, mTOR activation, autophagy, and cell proliferation were evaluated by Western blotting, flow cytometry, and functional assays. IgG from women with PM/VT increased HUVEC mitochondrial hyperpolarization and activation of the mTOR and autophagic pathways, while IgG from patients with VT induced endothelial autophagy and cell proliferation in the absence of elevated mTOR activity or mitochondrial dysfunction. IgG from the SN-OAPS patient group had no effect on any of these HUVEC responses. In conclusion, aPL from women with PM and vascular events induce cellular stress evidenced by mitochondrial hyperpolarization and increased activation of the mTOR and autophagic pathways which may play a role in the pathogenesis of obstetric APS.

Bleeding and antithrombotic therapy during pregnancy in women with poor aPL-related obstetric outcomes: A survey of 1075 cases from EUROAPS registry∗

BACKGROUND

The combination of low-dose aspirin (LDA) and low-molecular-weight heparin (LMWH) until the end of gestation are the currently the accepted standard of care for the treatment of antiphospholipid-related obstetric disorders. In refractory cases, hydroxychloroquine (HCQ) can be added to this standard of care.

OBJECTIVE

To evaluate the haemostatic safety of LDA and LMWH (medium to high prophylactic doses) during pregnancy and the puerperium in women with both full-blown obstetric antiphospholipid syndrome (OAPS) (Sydney criteria) and noncriteria - incomplete - OAPS.

STUDY DESIGN

Retrospective/prospective multicentre observational study. Obstetric background, laboratory categories, delivery mode, antithrombotic regimens and bleeding complications were compared.

SETTING

A total of 30 tertiary European hospitals.

PATIENTS

Mainly, Caucasian/Arian pregnant women were included. Other ethnicities were minimally present. Women were controlled throughout pregnancy and puerperium.

MAIN OUTCOME MEASURES

The primary end-point was to evaluate the number of major and minor haemorrhagic complications in this cohort of women. Neuraxial anaesthetic bleeding complications were particularly assessed. Secondly, we aimed to compare local/general bleeding events between groups.

RESULTS

We studied 1650 women, of whom 1000 fulfilled the Sydney criteria of the OAPS and 650 did not (noncriteria OAPS). Data on antithrombotic-related complications were available in 1075 cases (65.15%). Overall, 53 (4.93%) women had bleeding complications, with 34 being considered minor (3.16%) and 19 major (1.76%). Neither obstetric complications nor laboratory categories were bleeding-related. Assisted vaginal delivery and caesarean section were related to local haemorrhage. Heparin doses and platelet count were not associated with major bleeding.

CONCLUSIONS

LDA and medium to high prophylactic LMWH during pregnancy in women with full-blown OAPS/noncriteria OAPS are safe. A slight increase in bleeding risk was noted in instrumental deliveries. No women who underwent spinal or epidural anaesthesia suffered bleeding complications. No haemorrhage was observed in cases where HCQ was added to standard therapy.

Immunological and physiopathological approach of COVID-19 in pregnancy

Coronavirus disease-2019 (COVID-19) related to Coronavirus-2 (SARS-CoV-2) is a worldwide health concern. Despite the majority of patients will evolve asymptomatic or mild-moderate upper respiratory tract infections, 20% will develop severe disease. Based on current pathogenetic knowledge, a severe COVID-19 form is mainly a hyperinflammatory, immune-mediated disorder, triggered by a viral infection. Due to their particular immunological features, pregnant women are supposed to be particularly susceptible to complicate by intracellular infections as well as immunological disturbances. As an example, immune-thrombosis has been identified as a common immune-mediated and pathogenic phenomenon both in COVID-19, in obstetric diseases and in COVID-19 pregnant women. According to extensive published clinical data, is rationale to expect an interference with the normal development of pregnancy in selected SARS-CoV-2-infected cases, mainly during third trimester.This manuscript provides insights of research to elucidate the potential harmful responses to SARS-CoV-2 and /or other coronavirus infections, as well as bidirectional interactions between COVID-19 and pregnancy to improve their respective management.

Immunological Risk Factors in Recurrent Pregnancy Loss: Guidelines Versus Current State of the Art

Around 1-5% of all couples experience recurrent pregnancy loss (RPL). Established risk factors include anatomical, genetic, endocrine, and hemostatic alterations. With around 50% of idiopathic cases, immunological risk factors are getting into the scientific focus, however international guidelines hardly take them into account. Within this review, the current state of immunological risk factors in RPL in international guidelines of the European Society of Reproduction and Embryology (ESHRE), American Society of Reproductive Medicine (ASRM), German/Austrian/Swiss Society of Obstetrics and Gynecology (DGGG/OEGGG/SGGG) and the Royal College of Obstetricians and Gynecologists (RCOG) are evaluated. Special attention was drawn to recommendations in the guidelines regarding diagnostic factors such as autoantibodies, natural killer cells, regulatory T cells, dendritic cells, plasma cells, and human leukocyte antigen system (HLA)-sharing as well as treatment options such as corticosteroids, intralipids, intravenous immunoglobulins, aspirin and heparin in RPL. Finally, the current state of the art focusing on both diagnostic and therapeutic options was summarized.

Increased Peripheral NKG2A-NKG2D+CD3-CD16+CD56dim NK Cell Subset Was Positively Correlated with Antiphospholipid Antibodies in Patients of Obstetric Antiphospholipid Syndrome

Obstetric antiphospholipid syndrome (OAPS) is an autoimmune disorder with severe life-threatening complications shown during pregnancy. It has been reported that the increase in CD16⁺CD56^dim natural killer (NK) cells in peripheral blood are risk factors for recurrent miscarriages, but this expression of CD16⁺CD56^dim NK cells in OAPS patients has not been reported, and the mechanism is not clearly illustrated. In this study, we compared the distributional profiles of different NK cell subsets and the expressions of NK cell-activating receptors in peripheral blood of patients with OAPS and healthy women. Our results showed significantly increased NKG2A^-NKG2D⁺ subset and decreased NKG2A⁺NKG2D^- subset in CD3^- CD16⁺CD56^dim NK cells, CD3^-CD16^-CD56^bright NK cells and CD56⁺T cells in OAPS patients compared with those in healthy control women. The CD27^-CD11b⁺ subset significantly increased in CD3^-CD16⁺CD56^dim NK cells in OAPS patients compared with those in healthy control women. In addition, the NKG2A^-NKG2D⁺ subset in CD3^-CD16⁺CD56^dim NK subset in triple positivity was higher than single positivity OAPS patients. At the optimal diagnostic threshold established by ROC analysis, using the cut-off of NKG2A^-NKG2D⁺ and CD27^-CD11b⁺ subset in CD3^-CD16⁺CD56^dim NK cells is 10.10% and 92.75%, the sensitivity of NKG2A^-NKG2D⁺ and CD27^-CD11b⁺ to detect patients with OAPS compared with healthy control results was 94.1% and 60.8%, and specificity was 84.2% and 89.5%, respectively, with an area under the curve (AUC) of 0.903 and 0.829, respectively. The NKG2A^-NKG2D⁺ subset in CD3^-CD16⁺CD56^dim NK cells was positively correlated with the antiphospholipid antibodies lg anti-aCL IgG, lg anti-aCL IgM, lg anti-aCL IgA, lg anti-β2GP1 IgM and Complement 4(C4), while the CD27⁺CD11b⁺ subset in CD3^-CD16⁺CD56^dim NK cells was correlated with lg anti-β2GP1 IgG and lg anti-β2GP1 IgA. These results suggested that the NK cytotoxic function enhanced in OAPS patients and unbalanced of NK activating receptors and inhibiting receptors may contribute to the immune pathogenesis of OAPS.

Comparative study of obstetric antiphospholipid syndrome (OAPS) and non-criteria obstetric APS (NC-OAPS): report of 1640 cases from the EUROAPS registry

OBJECTIVES

To compare clinical features, laboratory data and fetal-maternal outcomes between 1000 women with obstetric APS (OAPS) and 640 with aPL-related obstetric complications not fulfilling Sydney criteria (non-criteria OAPS, NC-OAPS).

METHODS

This was a retrospective and prospective multicentre study from the European Registry on Obstetric Antiphospholipid Syndrome.

RESULTS

A total of 1650 women with 5251 episodes, 3601 of which were historical and 1650 latest episodes, were included. Altogether, 1000 cases (OAPS group) fulfilled the Sydney classification criteria and 650 (NC-OAPS group) did not. Ten NC-OAPS cases were excluded for presenting thrombosis during follow-up. All cases were classified as category I (triple positivity or double positivity for aPL) or category II (simple positivity). Overall, aPL laboratory categories showed significant differences: 29.20% in OAPS vs 17.96% in NC-OAPS (P < 0.0001) for category I, and 70.8% in OAPS vs 82% in NC-OAPS (P < 0.0001) for category II. Significant differences were observed when current obstetric complications were compared (P < 0.001). However, major differences between groups were not observed in treatment rates, livebirths and thrombotic complications. In the NC-OAPS group, 176/640 (27.5%) did not fulfil Sydney clinical criteria (subgroup A), 175/640 (27.34%) had a low titre and/or non-persistent aPL positivity but did meet the clinical criteria (subgroup B) and 289/640 (45.15%) had a high aPL titre but did not fulfil Sydney clinical criteria (subgroup C).

CONCLUSION

Significant clinical and laboratory differences were found between groups. Fetal-maternal outcomes were similar in both groups when treated. These results suggest that we could improve our clinical practice with better understanding of NC-OAPS patients.

Oxidative stress in endothelial cells induced by the serum of women with different clinical manifestations of the antiphospholipid syndrome

Introducción.

El síndrome antifosfolípido se caracteriza por la presencia persistente de anticuerpos antifosfolípidos y manifestaciones clínicas de trombosis o morbilidad gestacional, las cuales se asocian con estrés oxidativo y disfunción endotelial.

Objetivo.

Evaluar los marcadores de estrés oxidativo en células endoteliales, inducidos por el suero de mujeres con diferentes manifestaciones clínicas del síndrome antifosfolípido y analizar la capacidad antioxidante de los sueros.

Materiales y métodos.

Se incluyeron 48 mujeres que fueron clasificadas así: presencia de anticuerpos antifosfolípidos y criterios clínicos de morbilidad gestacional, trombosis vascular o ambas. Como grupos control se incluyeron mujeres negativas para anticuerpos antifosfolípidos. En un modelo in vitro de células endoteliales estimuladas con los sueros de las mujeres del estudio, se determinaron algunos marcadores de estrés oxidativo por citometría de flujo. También, se analizó la capacidad antioxidante de los sueros incluidos.

Resultados.

Los sueros de los grupos de mujeres con síndrome antifosfolípido que presentaban trombosis, con morbilidad gestacional o sin ella, generaron un incremento significativo (p<0,05 y p<0,001) en los marcadores de estrés oxidativo endotelial, en contraste con el control de suero humano normal. No se observaron diferencias en el efecto de los sueros de los diferentes grupos de estudio sobre la lipoperoxidación endotelial. Tampoco se encontró diferencia en la actividad antioxidante de los sueros.

Conclusión.

El estrés oxidativo mitocondrial en el endotelio se asocia con la presencia de trombosis. Sin embargo, cuando esta se asocia con morbilidad gestacional, también se genera estrés oxidativo intracelular.

Thromboprophylaxis in pregnant women with thrombophilia and a history of thrombosis

Background Despite intensive research, thromboembolism still accounts for significant maternal morbidity and mortality. We examined thrombophilia in patients with thromboembolism during pregnancy and evaluated the efficiency of antithrombotic prophylaxis in patients with thrombophilia for the prevention of recurrent thromboembolism. Materials and methods Sixty-eight women with a history of thromboembolism were managed during pregnancy, in light of their thrombotic history and the result of thrombophilia assessment. Group I (n=50) received prophylaxis with low molecular weight heparin (LMWH)±aspirin (50-100 mg/day) in preconception period or from the 1st trimester, during pregnancy and at least 6 weeks postpartum. Group II (n=18) received LMWH±aspirin from the II to III trimester. Results Thromboses were associated with pregnancy in 27 patients (39.7%), with systemic diseases - in nine (13.2%), oral contraceptives use - 22 (32.3%), immobilization due to surgery and/or trauma, long flight - six (8.9%), septic complications - two (2.9%). Nevertheless, 24.5% of patients had no apparent provoking factor for the development of thrombotic complications. Thirty-seven (54%) patients with venous thromboembolism (VTE) had familial history of VTE, and 25 (36.7%) had personal history of pregnancy complications (fetal loss syndrome, preeclampsia and placental abruption) (P<0.05 vs. control). Thrombophilia was detected in 58 (85.3%). Usual thrombogenic polymorphisms [factor V (FV) Leiden and prothrombin G20210A, heterozygous forms] were revealed in 16 (23.5%) and eight (11.7%) patients, respectively. Antiphospholipid antibodies (aPL) circulation was found in 34 (50%) patients. Non-usual thrombogenic polymorphisms were identified in 44 (64.7%) of the women and hyperhomocysteinemia - in 30 (44.2%). In group I no one had severe obstetric complications. All the patients were delivered at term and all the babies were alive. In group II moderate-to-severe obstetric complications were noted: preeclampsia - in 11 (16.2%), severe preeclampsia - seven (10.3%), preterm delivery - in 18 (26.4%) patients from subgroup II (P<0.05). Conclusions Women with a personal or a family history of thromboembolism and obstetric complications should be screened for thrombophilia. Beginning anticoagulant therapy early in such patients is effective not only for preventing recurring thrombosis but also preventing obstetric complications. Late prophylaxis after the completion of the trophoblast invasion therapy is much less effective.