Frequency of vascular and pregnancy morbidity in patients with low vs. moderate-to-high titers of antiphospholipid antibodies

Recurrent miscarriage and low-titer antiphospholipid antibodies

OBJECTIVE

To evaluate the clinical features and pregnancy outcomes in patients experiencing recurrent miscarriage (RM) with either low-titer or medium-high titer positivity of antiphospholipid antibodies (aPL).

METHODS

A retrospective review of medical records was conducted for patients with aPL positivity and recurrent miscarriage between 2018 and 2022. The clinical features, treatment strategies, outcomes were compared between the patients with low (n = 92) and medium (n = 32) titer of aPL.

RESULTS

A total of 118 patients, resulting in 124 obstetric episodes (pregnancies), with a mean age of 33. 15 ± 4.56 and 31.47 ± 4.41 years between the two groups. The low-titer group exhibited a higher frequency of anti-cardiolipin antibodies IgM (P < 0.001), whereas the medium-high titer group demonstrated a higher frequency of anti-β2-glycoprotein 1 antibodies IgG (P < 0.001) and IgM (P = 0.032). Moreover, the medium-high titer group displayed a significantly elevated erythrocyte sedimentation rate compared to the low-titer group (P < 0.05). In the low-titer group, 71 patients (77.2%) received appropriate treatment, resulting in 48 live births (67.6%) and 23 repeat abortions (32.4%). In the medium-high titer group, 29 patients (90.6%) received relevant treatment, leading to 23 live births (79.3%) and 6 repeat abortions (20.7%). No significant differences were observed in live births or maternal-fetal complications between the two groups (all P > 0.05).

CONCLUSION

Noteworthy distinctions in laboratory parameters were identified between the low-titer and medium-high titer groups. However, when appropriately treated, the fetal-maternal outcomes were comparable in both groups. Timely intervention by clinicians is imperative to enhance pregnancy outcomes in patients experiencing recurrent miscarriage with low levels of aPL. Key Points • This study challenges the conventional belief that only the higher antiphospholipid antibodies (aPL) titers directly correlated with worse pregnancy outcomes, which emphasized the importance of patients with low titer positive aPL-positive RM. • The results underscore the need for timely intervention in women with low titer aPL-positive RM, as it leads to favorable maternal-fetal outcomes.

"How we treat" clinical dilemmas in antiphospholipid syndrome: A case-based approach

Antiphospholipid syndrome (APS) is an autoimmune condition characterized by thrombosis (arterial, venous, and microvascular) and/or pregnancy morbidity occurring in subjects persistently positive for antiphospholipid antibodies (aPL). While the APS classification criteria are being currently updated to improve homogeneity in clinical research, patients who seek medical treatment often have a variety of laboratory and clinical characteristics that may not completely fulfill the classification criteria for overt APS. Those cases might represent a challenge in terms of treatment and overall management. We aim to present a collection of challenging scenarios of patients who tested positive for aPL and to discuss available literature to guide the therapeutic strategies.

Inactivation of Yes-Associated Protein Mediates Trophoblast Dysfunction: A New Mechanism of Pregnancy Loss Associated with Anti-Phospholipid Antibodies?

Pregnancy morbidity induced by anti-phospholipid antibodies (aPL+/PM+) is mainly thought to arise from placental abnormalities. We attempted to investigate the effect of aPL on the activity of Yes-associated protein (YAP) in the trophoblast and how YAP regulated human trophoblasts function. Thus, HTR-8 cells were treated with IgG purified from aPL+/PM+ women or normal controls. We found that aPL+/PM+ IgG impacted YAP activity via abrogating YAP expression. Further investigation of the anti-β2GPI-IgG/β2GPI complex showed an inhibition of nuclear YAP level and translocation in a dose-dependent manner, which might be rescued by progesterone in HTR-8 cells. YAP overexpression or knockdown HTR-8 cells were established for the evaluation of cell function and related gene expression in vitro. Loss of YAP arrested cell cycles in the G2/M phase, accelerated cell apoptosis by increasing the ratio of Bax/Bcl2, and disrupted MMP2/9-mediated cell migration and angiogenesis tube formation by VEGF. These findings support a new mechanism of PM associated with aPL through which YAP inactivation induced by aPL perturbs the trophoblast cell cycle, apoptosis, migration, and angiogenesis, finally developing into pregnancy failure.

Non-Criteria Obstetric Antiphospholipid Syndrome: How Different Is from Sidney Criteria? A Single-Center Study

This study aims to compare the demographic characteristics, clinical features, serology, and fetal-maternal outcomes between women with obstetric antiphospholipid syndrome (APS) and those with non-criteria (NC)-APS and seronegative (SN)-APS. Two-hundred and sixty-three women with APS obstetric morbidity ever pregnant were included. Of those, 66 met the APS classification criteria, 140 were NC-APS, and 57 were SN-APS. Patients with other autoimmune diseases were excluded. Adverse pregnancy outcomes (APO) included early pregnancy loss, fetal death, preeclampsia, abruptio placentae, and preterm birth. The mean age of the study group was 33.6 ± 5.3 years, and patients were followed up for 129.5 ± 81.9 months. In the NC-APS group, 31 (22.1%) did not fulfill clinical and serological criteria (Subgroup A), 49 (35%) did meet clinical but not serologic criteria (Subgroup B), and 60 (42.9%) fulfilled the serologic criteria but not the clinical ones (Subgroup C). The cardiovascular risk burden was higher in the APS group, due to a higher proportion of smoking. Patients with criteria APS received more intensive treatment than patients in the other study groups. The addition of standard of care (SoC) treatment significantly improved live birth and decreased APO in all groups. Significant clinical differences were observed between the study groups. However, when treated with SoC, fetal-maternal outcomes were similar, with a significant improvement in live births and a decrease in APO. Risk stratification in patients with obstetric morbidity associated with APS can help individualize their treatment.

Comparison of non-criteria antiphospholipid syndrome with definite antiphospholipid syndrome: A systematic review

Objectives

Patients with laboratory or clinical manifestations suggestive of antiphospholipid syndrome (APS) but not fulfilling the classification criteria constitute a clinical challenge. This study aims to compare non-criteria APS (NC-APS) with definite APS in terms of clinical manifestations, therapies, and outcomes.

Methods

A systematic review of observational studies comparing definite and NC-APS was performed searching four electronic databases. Data on clinical manifestations, therapies and clinical outcomes was extracted.

Results

Sixteen studies, assessing a total of 3,798 participants, were included. Seven out of 10 studies found no significant difference in the prevalence of arterial or venous thrombosis between definite and NC-APS, with two studies on seronegative APS also finding no difference in thrombosis recurrence. Seven out of 12 studies found no significant difference in the prevalence of obstetric manifestations between groups, with the remaining exhibiting conflicting results. In 9 studies comparing treatment frequency in obstetric patients, all but one described similar treatment frequency, with the percentage of NC-APS treated during pregnancy ranging from 26% to 100%. In 10 studies comparing pregnancy outcomes of NC-APS versus definite APS, 7 found similar successful pregnancies/live births. Additionally, 5 studies described improvement of live births in both groups with treatment, with three signalling aspirin monotherapy as efficacious as combination therapy in NC-APS.

Conclusion

This review hints at an absence of marked differences in most evaluated parameters between definite and NC-APS, emphasizing the value of a more active follow-up of these patients. The low-quality available evidence highlights the need for well-defined NC-APS populations in future studies.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero, identifier CRD42020210674.

Comparing pregnancy outcomes in patients with criteria and non-criteria autoimmune disease: A systematic review

BACKGROUND

Not all patients fulfil criteria for specific autoimmune rheumatic diseases (ARDs) and are then defined as having non-criteria (nc)ARD. It is uncertain whether well-recognised associations with adverse pregnancy outcomes in patients with criteria ARD also exist in patients with ncARD or undifferentiated connective tissue disease (UCTD). Therefore, we undertook a systematic review of the prevalence of adverse pregnancy outcomes in various ncARD and UCTD compared with criteria ARD to identify whether there are increased risks and to examine for any benefits of treatment.

METHODS

This study was conducted in accordance with the guidance of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standard. A systematic literature review was performed using online databases including Medline and PubMed from inception to the beginning of April 2021 using appropriate keywords for various ARD and pregnancy outcomes.

RESULTS

After screening 665 articles, 36 articles were chosen for full text review and 15 selected for final analysis. There were eight studies of nc antiphospholipid syndrome (APS) of more than 7000 pregnancies and seven studies of UCTD of more than 1000 pregnancies. No studies of any other ncARD in pregnancy were identified. We found that patients with either ncAPS or UCTD seem to have an increased burden of poor pregnancy outcomes compared with the general population. Despite the heterogeneity and poor quality of the studies, we also noted that ncAPS and criteria APS patients may have similar rates of obstetric complications with standard and/or non-standard APS treatment regimens.

CONCLUSION

Our findings of increased risks of poor pregnancy outcomes in patients with ncAPS or UCTD will be helpful for pre-pregnancy counselling and management of these patients in pregnancy and support their referral to specialist obstetric-rheumatology and obstetric-haematology clinics.

EUREKA algorithm predicts obstetric risk and response to treatment in women with different subsets of anti-phospholipid antibodies

OBJECTIVES

aPL, the serum biomarkers of APS, are the most common acquired causes of pregnancy morbidity (PM). This study investigates the impact of aPL positivity fulfilling classification criteria ('criteria aPL') and at titres lower than thresholds considered by classification criteria ('low-titre aPL') on PM and assesses the effectiveness of low-dose aspirin (LDASA), low molecular weight heparin (LMWH) and HCQ in reducing the probability of PM (PPM).

METHODS

Longitudinal data on 847 pregnancies in 155 women with persistent aPL at any titre and 226 women with autoimmune diseases and negative aPL were retrospectively collected. A generalized estimating equations model for repeated measures was applied to quantify PPM under different clinical situations.

RESULTS

EUREKA is a novel algorithm that accurately predicts the risk of aPL-associated PM by considering aPL titres and profiles. aPL significantly impact PPM when at low titres and when fulfilling classification criteria. PPM was further stratified upon the aPL tests: aCL IgG/IgM and anti-β2-glycoprotein I (β2GPI) IgM, alone or combined, do not affect the basal risks of PPM, an increase occurs in case of positive LA or anti-β2GPI IgG. LDASA significantly affects PPM exclusively in women with low-titre aPL without anti-β2GPI IgG. The LDASA + LMWH combination significantly reduces PPM in all women with low-titre aPL and women with criteria aPL, except those carrying LA and anti-β2GPI IgG. In this group, the addition of HCQ further reduces PPM, although not significantly.

CONCLUSION

EUREKA allows a tailored therapeutic approach, impacting everyday clinical management of aPL-positive pregnant women.

Management of patients with antiphospholipid antibodies: what to do in laboratory scenarios that do not fit the guidelines

Introduction: Some patients with positive antiphospholipid antibodies (aPL) have not been included in randomized clinical trials or observational registries and, therefore, information on their risk of obstetric or thrombotic recurrence and optimal treatment is scarce.Areas covered: In the present review, the existing evidence regarding the management of two laboratory scenarios not covered by the guidelines is presented: (1) patients with antiphospholipid syndrome (APS) clinical manifestations and aPL positivity not fulfilling APS laboratory criteria, and (2) the possibility of discontinuing anticoagulation in APS patients whose aPL become persistently negative.Expert opinion: Growing evidence suggests a role for low titers and 'non-criteria' aPL, especially in obstetric APS. Treatment is not formally recommended but might be considered according to the individual's risk profile. Regarding the question of whether or not to discontinue anticoagulants after the 'spontaneous' disappearance of aPL, there is no definite answer. Retrospective studies seem to suggest that withdrawal of anticoagulation could be safe in certain patients with APS, especially in those with a first provoked venous thrombosis and whose aPL became persistently negative during follow-up. Still, before the withdrawal can be recommended in routine clinical practice, multicenter and prospective studies are required to validate this hypothesis.

"Non-criteria" antiphospholipid syndrome: A nomenclature proposal

The classification criteria for antiphospholipid syndrome (APS) generate discussion, with a growing impression that certain patients not fulfilling these criteria might be inadequately excluded from the classification. Nonetheless, these "non-criteria" patients are heterogeneously defined across different publications. We reviewed the "non-criteria" APS subgroups depicted in the literature and attempted to organize these subsets in a nomenclature proposal that could be used for research purposes. We established four potential patient profiles, grouped under the broad term "non-criteria APS": (A) "Seronegative APS": patients fulfilling clinical criteria, plus "non-criteria" manifestations, with persistently negative antiphospholipid antibodies (aPL); (B) "Clinical non-criteria APS": patients with "non-criteria" manifestations, plus aPL positivity fulfilling the classification criteria; (C) "Incomplete laboratory APS": patients fulfilling clinical criteria, plus positive aPL, but not fulfilling the classification criteria (low titer aPL); and (D) "Laboratory non-criteria APS": patients fulfilling clinical criteria, with negative or low titer criteria aPL, plus positive "non-criteria" aPL. This categorization could allow for a more homogeneous research approach to APS, enabling more sustained and universal conclusions.

Anti-phospholipid antibodies and reproductive failures

Anti-phospholipid syndrome (APS) recapitulates the link between autoimmunity and pregnancy failure: Acquired anti-phospholipid antibodies (aPL) play a pathogenic role in pregnancy complications. The diagnosis of obstetric APS can easily be pursued when women present with laboratory and clinical features fulfilling the international classification criteria. Standard therapeutic approach to obstetric APS consists in the association of anti-platelet agents and anticoagulants. Most patients achieve a live birth thanks to conventional treatment; however, approximately 20% fail to respond and are managed with additional therapeutic tools added on the top of conventional treatment. Surely, a refinement of risk stratification tools would allow early identification of high-risk pregnancies that warrant tailored treatment. In real life, obstetricians and rheumatologists face complex diagnostic scenarios including women with pregnancy morbidities other than those mentioned in classification criteria such as one or two early losses and premature birth after 34 weeks due to preeclampsia or placental insufficiency, women with low-titer aPL not fulfilling criteria laboratory requirements, women with positive non-criteria aPL, asymptomatic aPL carriers, and infertile women found to be aPL-positive. This review focuses on some of the several unanswered questions related to diagnostic, prognostic, and therapeutic aspects in obstetric APS.

Obstetric and vascular antiphospholipid syndrome: same antibodies but different diseases?

Recurrent thrombosis and miscarriages are the main clinical manifestations of antiphospholipid syndrome (APS). Although most patients display both clinical signs, some patients can have isolated vascular or obstetric variants. Emerging data raise the question of whether obstetric and vascular APS are the same or different diseases. An important difference between the two conditions is that a thrombophilic state is a common feature in vascular APS, whereas clot occlusions of the decidual spiral arteries are seldom observed in obstetric APS, and infarctions are found in only one-third of APS placentae. Conversely, inflammation, which is undetectable in vascular APS, is frequently observed in the placentae of patients with obstetric APS and has been documented in the placentae of pregnant mice with fetal loss mediated by antiphospholipid antibodies. Attempts to identify different antibodies or epitopes responsible for the two clinical manifestations of APS have so far been unsuccessful. Possible mechanisms exist that might explain the development of the two clinical presentations, including the tissue distribution and expression level of the main target antigen of antiphospholipid antibodies, β2 glycoprotein I (β2GPI). The identification of the factors that promote the onset of either obstetric or vascular APS has important diagnostic and therapeutic implications.

The association between antiphospholipid antibodies and late fetal loss: A systematic review and meta-analysis

INTRODUCTION

Antiphospholipid syndrome is a chronic autoimmune disease with a high prevalence in females. Published data have identified that antiphospholipid antibodies (APLA) of antiphospholipid syndrome are risk factors for poor pregnancy outcomes, such as recurrent spontaneous abortion, intrauterine growth restriction and preeclampsia. However, the association between APLA and late fetal loss is not fully understood and remains controversial. The aim of this study is to identify and analyze the recent publications to better understand the association between APLA and late fetal loss.

MATERIAL AND METHODS

The literature was searched on 31 January 2019 using Ovid, Medline, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL) to evaluate the association between APLA and late fetal loss, with articles published before January 2019, according to the PRISMA statement. Without imposing regional restrictions, referenced articles were selected. Quality assessment was conducted independently by two reviewers, based on the Newcastle-Ottawa scale. For the meta-analysis, we used odds ratios (random effects model). The between-study heterogeneity was assessed by Q test. Publication bias was assessed by funnel plots.

RESULTS

Nineteen studies (with 10 265 cases) were included in the final analysis. The odds ratio (OR) for the late fetal loss with lupus anticoagulant was 5.02 (95% confidence interval [CI] 2.14-7.89). Seven included studies reported that lupus anticoagulant had a statistically significant association with late fetal loss. The results did not show a statistically significant association between anticardiolipin antibodies and late fetal loss. The pooled odds ratio for the association of anticardiolipin antibodies with late fetal loss was 3.47 (95% CI 0.68-6.26). However, we did find the relation between anticardiolipin antibodies and late fetal loss among cohort studies (OR 2.27, 95% CI 1.20-3.44). Anti-beta2 glycoprotein 1 antibodies (β2GP1) showed a significant association with late fetal loss (OR 3.13, 95% CI 0.75-5.50).

CONCLUSIONS

Lupus anticoagulant is strongly associated with late fetal loss in antiphospholipid syndrome patients. However, the association between anticardiolipin antibodies and late fetal loss is inconsistent. There are currently insufficient data to support a significant relation between β2GP1 and late fetal loss.

Antiphospholipid syndrome in obstetrics

Antiphospholipid syndrome (APS) covers a spectrum of clinical manifestations ranging from recurrent pregnancy loss and obstetric complications from placental dysfunction through to thrombotic disease. This article will focus on the common manifestations of the pregnancy-related complications of APS. This includes clinical manifestations, diagnosis and management, as general practitioners will need to be able to recognize the disorder and will also have patients under their care receiving treatment for APS.

Obstetric Anti-phospholipid Syndrome: State of the Art

PURPOSE OF REVIEW

This review focuses on new pathogenesis and clinical-therapeutic aspects of obstetric anti-phospholipid syndrome (ob-APS) in the last 5 years.

RECENT FINDINGS

The pathogenesis of ob-APS is multifactorial, including placental infarctions, infiltration of inflammatory cells that cause acute and chronic inflammation, leading to uncontrolled inflammation and poor pregnancy outcomes. A preconception counseling and a patient-tailored treatment are fundamental to improve maternal and fetal outcomes. Thanks to conventional treatment, based on low-dose aspirin and heparin, 70% of women with ob-APS can have successful pregnancies. Women with positive anti-phospholipid antibodies (aPL) without clinical manifestations ("aPL carriers") or with obstetric manifestation not fulfilling ob-APS criteria need to be further investigated in order to assess their best management. Great interest has been given to drugs that could interact in the pathophysiological mechanisms, such as hydroxychloroquine, statins, and eculizumab. These drugs could be considered for patients refractory to conventional therapy.

Current insights in obstetric antiphospholipid syndrome

PURPOSE OF REVIEW

Antiphospholipid syndrome (APS) is defined as the association of thrombotic events and/or obstetric morbidity in patients persistently positive for antiphospholipid antibodies (aPL). In this review, we will highlight the most important clinical presentations of APS with a focus on the obstetric morbidity, the current management strategies and the outlook for the future.

RECENT FINDINGS

The use of aspirin and heparin has improved the pregnancy outcome in obstetric APS and approximately 70% of pregnant women with APS have a successful pregnancy outcome. Unfortunately, the current standard of care does not prevent all pregnancy complications as the current treatment fails in 20-30% of APS pregnancies. This therefore highlights the need for alternative treatments to improve obstetrical outcome. Other treatment options are currently explored and retrospective studies show that pravastatin for example is beneficial in women with aPL-related early preeclampsia. Moreover, the immunmodulator hydroxychloroquine may play a beneficial role in the prevention of aPL-related pregnancy complications.

SUMMARY

APS is among the most frequent acquired risk factors for a treatable cause of recurrent pregnancy loss and increases the risk of conditions associated with ischaemic placental dysfunction, such as fetal growth restriction, preeclampsia, premature birth and intrauterine death. Current treatment is mainly based on aspirin and heparin. Studies to inform on alternative treatment options are urgently needed.

Comparative study between obstetric antiphospholipid syndrome and obstetric morbidity related with antiphospholipid antibodies

BACKGROUND AND OBJECTIVES

To compare clinical, laboratory, treatment and live birth rate data between women with aPL-related obstetric complications (OMAPS) not fulfilling the Sydney criteria and women fulfilling them (OAPS).

MATERIALS AND METHODS

Retrospective and prospective multicentre study. Data comparison between groups from The European Registry on Antiphospholipid Syndrome included within the framework of the European Forum on Antiphospholipid Antibody projects.

RESULTS

338 women were analysed: 247 fulfilled the Sydney criteria (OAPS group) and 91 did not (OMAPS group). In the OMAPS group, 24/91 (26.37%) fulfilled laboratory Sydney criteria (subgroup A) and 67/91 (74.63%) had a low titre and/or non-persistent aPL-positivity (subgroup B). Overall, aPL laboratory categories in OAPS vs. OMAPS showed significant differences: 34% vs. 11% (p<0.0001) for category I, 66% vs. 89% (p<0.0001) for category II. No differences were observed when current obstetric complications were compared (p=0.481). 86.20% of OAPS women were treated vs. 75.82% of OMAPS (p=0.0224), particularly regarding the LDA+LMWH schedule (p=0.006). No differences between groups were observed in live births, gestational, puerperal arterial and/or venous thrombosis.

CONCLUSIONS

Significant differences were found among aPL categories between groups. Treatment rates were higher in OAPS. Both OAPS and OMAPS groups had similarly good foetal-maternal outcomes when treated. The proposal to modify OAPS classification criteria, mostly laboratory requirements, is reinforced by these results.

Subsequent Thrombotic Outcomes in Patients with Ischemic Stroke with Antiphospholipid Antibody Positivity

PURPOSE

International consensus criteria for antiphospholipid syndrome (APS) require persistently positive antiphospholipid antibodies (aPL) and medium or high titers in association with clinical manifestations. However, the clinical relevance of persistence and titers of aPL in patients with stroke has not been identified. We aimed to investigate the risk of subsequent thrombotic events in patients with ischemic stroke with aPL positivity in terms of aPL status.

MATERIALS AND METHODS

We reviewed the medical records of 99 patients with ischemic stroke with at least one or more aPL-positivity (i.e., positivity for aCL, anti-β2-glycoprotein-1, and/or lupus anticoagulants). The patients were divided into two groups: "definite APS" who fulfilled the laboratory criteria and "indefinite APS" who fell short of the criteria. We compared the risk of subsequent thrombotic events between the two groups. Cox proportional hazards model and Kaplan-Meier survival curves were used for the analyses.

RESULTS

Of the 99 patients, 46 (46%) were classified as having definite APS and 53 (54%) as having indefinite APS. The mean follow-up was 51.6 months. Overall event numbers were 14 (30.4%) in definite APS and 16 (30.2%) in indefinite APS. Increased subsequent thrombotic events (hazard ratio 1.039; 95% confidence interval 0.449-2.404; p=0.930) and decreased time to thrombotic events (log-rank p=0.321) were not associated with aPL status.

CONCLUSION

There was no increased risk of subsequent thrombotic events in ischemic stroke patients with definite APS, compared with those with indefinite APS.