"Non-criteria" antiphospholipid syndrome: A nomenclature proposal

Risk Factors for Antiphospholipid Antibodies and Antiphospholipid Syndrome

Persistence of serum antiphospholipid antibodies (aPL) is associated with a high thrombotic risk, both arterial and venous, and with pregnancy complications. Due to the potential morbidity and mortality associated with the presence of aPL, identifying and recognizing risk factors for the development of aPL and thrombosis in aPL carriers may help to prevent and reduce the burden of disease. Multiple elements are involved in the pathomechanism of aPL development and aPL-related thrombosis such as genetics, malignancy, and infections. This review will address the role of both well-known risk factors and their evolution, and of emerging risk factors, including COVID-19, in the development of aPL and thrombosis in aPL carriers.

Interaction of antiphospholipid antibodies with endothelial cells in antiphospholipid syndrome

Antiphospholipid syndrome (APS) is an autoimmune disease with arteriovenous thrombosis and recurrent miscarriages as the main clinical manifestations. Due to the complexity of its mechanisms and the diversity of its manifestations, its diagnosis and treatment remain challenging issues. Antiphospholipid antibodies (aPL) not only serve as crucial "biomarkers" in diagnosing APS but also act as the "culprits" of the disease. Endothelial cells (ECs), as one of the core target cells of aPL, bridge the gap between the molecular level of these antibodies and the tissue and organ level of pathological changes. A more in-depth exploration of the relationship between ECs and the pathogenesis of APS holds the potential for significant advancements in the precise diagnosis, classification, and therapy of APS. Many researchers have highlighted the vital involvement of ECs in APS and the underlying mechanisms governing their functionality. Through extensive in vitro and in vivo experiments, they have identified multiple aPL receptors on the EC membrane and various intracellular pathways. This article furnishes a comprehensive overview and summary of these receptors and signaling pathways, offering prospective targets for APS therapy.

Risk factors for thrombotic events in systemic lupus erythematosus patients with antiphospholipid antibodies: insights from morphometric measurements of carotid arteries

Objective

To identify the correlation between thrombosis and atherosclerosis in systemic lupus erythematosus (SLE) patients with antiphospholipid antibodies (aPLs) (SLE/aPLs) through high-resolution magnetic resonance imaging (HR-MRI) of the carotid artery.

Methods

A single-center, cross-sectional study was conducted. We collected consecutive patients with SLE/aPLs and healthy controls who underwent carotid HR-MRI examinations. The morphometric characteristics of the common carotid artery (CCA), internal carotid artery (ICA), external carotid artery (ECA), and carotid bulb (Sinus) were measured, and the differences in morphometric parameters between different groups were analyzed.

Results

A total of 144 carotid arteries were analyzed. Compared with the control group, the wall area, wall thickness (WT and WTmax), and normalized wall index of CCA, ICA, ECA, and Sinus were increased in patients with SLE/aPLs, and the total vascular area (TVA) of CCA, ICA, and Sinus, and the bifurcation angle (BIFA) of ICA-ECA were also increased. A negative lupus anticoagulant (LAC) (with or without positive anticardiolipin antibody (aCL) or anti-β2glycoprotein antibody (aβ2GPI)) contributed to illustrating lower increased TVA and thickened vessel walls of CCA and ICA in SLE/aPLs patients without thrombotic events. Logistic regression analysis showed that WTmaxSinus and WTmaxGlobal were independent risk factors for thrombotic events in SLE/aPLs patients. The receiver operator characteristic curve showed that the cut-off value of WTmaxSinus was 2.855 mm, and WTmaxGlobal was 3.370 mm.

Conclusion

HR-MRI ensures the complete and accurate measurement of carotid morphometric parameters. Compared with the control group, the carotid artery in patients with SLE/aPLs is mainly characterized by diffusely thickened vessel walls, and the patients with thrombotic events showed additional higher vascular area of CCA and ICA, and BIFA of ICA-ECA without significant change in lumen area. The carotid arteries of SLE/aPLs patients with thrombotic events exhibited significant vessel wall thickening in all segments except ECA compared to those without thrombotic events. LAC-negative and non-thrombotic events distinguish relatively early atherosclerosis in the carotid arteries in patients with SLE/aPLs. Patients with SLE/aPLs that possess circumscribed thickened carotid vessel walls (>3.370 mm), particularly thickened at the Sinus (>2.855 mm), may require management strategies for the risk of thrombotic events.

Impact of Inherited Thrombophilia in Women with Obstetric Antiphospholipid Syndrome: A Single-Center Study and Literature Review

Inherited thrombophilia (IT) has been implicated as a potential causal factor of adverse pregnancy outcomes (APOs), including recurrent miscarriage with and without the presence of antiphospholipid syndrome (APS). The aim of this study was to assess the prevalence and impact of IT on fetal-maternal outcomes and thrombotic risk in women within the spectrum of obstetric APS. Three hundred and twenty-eight women with APS-related obstetric morbidity ever pregnant were included. Of these, 74 met the APS classification criteria, 169 were non-criteria (NC)-APS, and 85 were seronegative (SN)-APS. Patients with other autoimmune diseases were excluded. APOs included early pregnancy loss, fetal death, preeclampsia, abruptio placentae, and preterm birth. Successful pregnancy was defined as the achievement of a live newborn. A literature search was also performed. The mean age of the overall group was 33.9 ± 5.3 years, and the patients were followed up for 35 (11-79) months. During the study period, there were 1332 pregnancies. Nearly 14% of the patients had an associated IT. IT patients more frequently received the standard-of-care (SoC) therapy. The presence of IT was not associated with worse maternal-fetal outcomes in patients treated with SoC treatment. Overall, IT patients had a lower frequency of newborns without treatment, especially those without definite APS. In addition, IT did not increase the risk of thrombosis during pregnancy or the postpartum period. A detailed analysis of the literature review identified only four publications related to our study and did not show conclusive evidence of the impact of IT on patients with obstetric APS. The group of women with APS-related obstetric morbidity and IT who did not receive treatment, especially those without definite APS, had a worse prognosis in terms of a live birth. However, with SoC therapy, the prognosis is similar in those patients without IT. The association of IT with APS does not seem to predispose to the development of thrombosis during pregnancy and/or the postpartum period.

Noncriteria antiphospholipid antibodies in antiphospholipid syndrome

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by thrombotic manifestations and/or obstetric complications in patients with persistently positive antiphospholipid antibodies (aPL). aPL are a heterogeneous group of autoantibodies, but only lupus anticoagulant, anticardiolipin (aCL), and antibeta2-glycoprotein I antibodies (aβ2GPI) IgG or IgM are included as laboratory classification criteria. Seronegative APS patients are usually defined as patients with the clinical symptoms of APS but who test negative for aPL. The negativity to classic aPL criteria does not exclude the presence of other aPL. Several noncriteria aPL have been identified. Some noncriteria aPL are well studied, such as IgA aCL and aβ2GPI, the antiphosphatidylserine-prothrombin (aPS/PT) antibodies, and the antibodies against the domain I of beta2-glycoprotein I (aDI), both latter groups receiving more attention for their role in thrombotic events and pregnancy complications. Other noncriteria aPL that have been studied are antibodies against annexin V, prothrombin, phosphatidylethanolamine, phosphatidic acid, phosphatidylserine, phosphatidylinositol, vimentin-cardiolipin complex, anti-protein S/protein C. Measurement of some of these noncriteria aPL (aPS/PT, aDI) is useful in the laboratory work-out of APS in specific situations. We have to differentiate between patients who are positive for noncriteria aPL only, and patients who have both criteria and noncriteria aPL to enable us to study their role in the diagnosis or risk stratification of APS. The research on noncriteria aPL is continually developing as the clinical relevance of these antibodies is not yet fully clarified.

Pattern of disease expression in SLE patients with antiphospholipid antibodies: data from Indian Systemic Lupus Erythematosus Inception cohort (INSPIRE)

Antiphospholipid antibodies (APLA) are present in one-third of systemic lupus erythematosus (SLE) patients, and they are associated with both criteria and non-criteria manifestations. We studied the prevalence, clinical associations, and impact on mortality of APLA in SLE patients from India. Among the Indian SLE inception cohort (INSPIRE), patients who had data on all five routinely performed APLAs [lupus anticoagulant (LA), IgG and IgM anticardiolipin antibody (aCL) and anti-β2-glycoprotein I(β2GPI)] at enrolment were selected. Patients were divided into four categories based on the presence/absence of APLA associated manifestations and presence/absence of the APLA viz SLE-APS, SLE-APLA, SLE: events but no APLA, and SLE: no events, no APLA (reference group). 1035 SLE patients at least 1 APLA antibody was detected in 372 (35.9%). LA was present in 206 (19.9%), aCL in 126 (12.2%) and β2-GPI in 178 (17.2%). There were 88 thrombotic events in 83 patients (8.0%); 73 (82.9%) being arterial; APLA positivity was present in 37 (44.6%) [AOR 1.70 (1.054, 2.76)]. SLE-APS patients were younger and had higher mortality [AOR 4.11 (1.51, 11.3)], neuropsychiatric and hematologic disease. SLE-APLA also had a higher mortality rate [AOR 2.94 (1.06, 8.22)] than the reference group. The mortality was highest in the subset of patients with thrombotic events in the presence of APLA [AOR 7.67 (1.25, 46.9)]. The mere presence of APLA also conferred higher mortality even in the absence of thrombotic events [AOR 3.51 (1.43, 8.63)]. Hematologic manifestations (36.1%) were the most common non-criteria-manifestation. One-third of SLE patients have APLA and its presence is associated with non-criteria hematologic manifestations, arterial thrombosis and higher mortality rate.

Antiphospholipid antibody-related hepatic vasculitis in a juvenile after non-severe COVID-19: a case report and literature review

Antiphospholipid antibodies (aPL) are both laboratory evidence and causative factors for a broad spectrum of clinical manifestations of antiphospholipid syndrome (APS), with thrombotic and obstetric events being the most prevalent. Despite the aPL-triggered vasculopathy nature of APS, vasculitic-like manifestations rarely exist in APS and mainly appear associated with other concurrent connective tissue diseases like systemic lupus erythematous. Several studies have characterized pulmonary capillaritis related to pathogenic aPL, suggesting vasculitis as a potential associated non-thrombotic manifestation. Here, we describe a 15-year-old girl who develops hepatic infarction in the presence of highly positive aPL, temporally related to prior non-severe COVID-19 infection. aPL-related hepatic vasculitis, which has not been reported before, contributes to liver ischemic necrosis. Immunosuppression therapy brings about favorable outcomes. Our case together with retrieved literature provides supportive evidence for aPL-related vasculitis, extending the spectrum of vascular changes raised by pathogenic aPL. Differentiation between thrombotic and vasculitic forms of vascular lesions is essential for appropriate therapeutic decision to include additional immunosuppression therapy. We also perform a systematic review to characterize the prevalence and clinical features of new-onset APS and APS relapses after COVID-19 for the first time, indicating the pathogenicity of aPL in a subset of COVID-19 patients.

Epidemiology of thromboembolic events in children and adolescents with antiphospholipid syndrome: A systematic review with meta-analysis

BACKGROUND AND AIM

This was a systematic review and meta-analysis of the prevalence of thromboembolic events in children and adolescents with antiphospholipid syndrome (APS).

METHODS

We searched PubMed, EMBASE and Web of Science to select relevant articles published between 1 January 2000 and 27 February 2022. We used the random-effects meta-analysis to estimate pooled point prevalence rates of thromboembolic events in studies with a minimum sample size of 30.

RESULTS

We included five studies reporting data of 336 children and adolescents with primary APS and secondary APS (SAPS). Pooled point prevalence rates of initial general thrombosis, arterial thrombosis, venous thrombosis and stroke in individuals with seropositive APS were 98.2% (95% confidence interval [CI] 87.5-100), 27.6% (95% CI 21.4-34.2), 51.1% (95% CI 38.2-63.9) and 13.4% 95% CI (6.3-22.7), respectively. Pooled point prevalence rates of initial arterial and venous thromboses in children and adolescents with SAPS were 45.7% (95% CI 21.1-71.6) and 29.2% (95% CI 14.8-46), respectively.

CONCLUSION

Arterio-venous thromboembolism is highly frequent in children and adolescents with SAPS. More studies using thrombotic and non-thrombotic APS classification criteria are warranted to better assess the frequency and predictors of thromboembolism in age- and ancestry-diverse pediatric populations affected by different types of APS.

A case of repeated in-stent restenosis of coronary artery as a primary manifestation of seronegative antiphospholipid antibody syndrome

BACKGROUND

Antiphospholipid antibody syndrome (APS) is a multisystemic autoimmune disorder which affects many organs or systems; however, coronary artery is relatively less frequently involved.

CASE PRESENTATION

A 65-year-old female with effort chest pain was hospitalized for unstable angina in Janurary, 2015. Coronary angiography revealed sub-total occlusion of proximal left anterior descending (LAD) coronary artery, where a drug-eluting stent was successfully deployed. The patient experienced multiple in-stent stenosis at LAD coronary artery and coronary artery bypass graft (CABG) surgery was advised. Subsequently, severe stenosis of left circumflex (LCX) coronary artery emerged, and the patient suffered persistent in-stent restenosis. Eventually, the patient was diagnosed with seronegative antiphospholipid antibody syndrome and salvaged by immunosuppressants.

CONCLUSIONS

Repeated in-stent restenosis could be a primary manifestation of seronegative antiphospholipid antibody syndrome, and suppression of autoimmune activity and inflammation other than purely coronary revascularization might be a better option.

High-throughput sequencing technology facilitates the discovery of novel biomarkers for antiphospholipid syndrome

Antiphospholipid syndrome (APS) is characterized by arterial and venous thrombosis and/or morbid pregnancy, accompanied by persistent antiphospholipid antibody (aPL) positivity. However, due to the complex pathogenesis of APS and the large individual differences in the expression of aPL profiles of patients, the problem of APS diagnosis, prognosis judgment, and risk assessment may not be solved only from the antibody level. It is necessary to use new technologies and multiple dimensions to explore novel APS biomarkers. The application of next-generation sequencing (NGS) technology in diseases with a high incidence of somatic mutations, such as genetic diseases and tumors, has been very mature. Thus, we try to know the research and application progress of APS by NGS technology from genome, transcriptome, epigenome and other aspects. This review will describe the related research of NGS technology in APS and provide more reference for the deep understanding of APS-related screening markers and disease pathogenesis.

Identifying high-risk profile in primary antiphospholipid syndrome through cluster analysis: French multicentric cohort study

INTRODUCTION

Antiphospholipid syndrome (APS) is an autoimmune disease characterised by thrombosis (arterial, venous or small vessel) or obstetrical events and persistent antiphospholipid antibodies (aPL), according to the Sydney classification criteria. Many studies have performed cluster analyses among patients with primary APS and associated autoimmune disease, but none has focused solely on primary APS. We aimed to perform a cluster analysis among patients with primary APS and asymptomatic aPL carriers without any autoimmune disease, to assess prognostic value.

METHODS

In this multicentre French cohort study, we included all patients with persistent APS antibodies (Sydney criteria) measured between January 2012 and January 2019. We excluded all patients with systemic lupus erythematosus or other systemic autoimmune diseases. We performed hierarchical cluster analysis on the factor analysis of mixed data coordinates results with baseline patient characteristics to generate clusters.

RESULTS

We identified four clusters: cluster 1, comprising 'asymptomatic aPL carriers', with low risk of events during follow-up; cluster 2, the 'male thrombotic phenotype', with older patients and more venous thromboembolic events; cluster 3, the 'female obstetrical phenotype', with obstetrical and thrombotic events; and cluster 4, 'high-risk APS', which included younger patients with more frequent triple positivity, antinuclear antibodies, non-criteria manifestations and arterial events. Regarding survival analyses, asymptomatic aPL carriers relapsed less frequently than the others, but no other differences in terms of relapse rates or deaths were found between clusters.

CONCLUSIONS

We identified four clusters among patients with primary APS, one of which was 'high-risk APS'. Clustering-based treatment strategies should be explored in future prospective studies.

Patients with laboratory criteria of anti-phospholipid syndrome and 'non-criteria' manifestations: a multicenter cohort

OBJECTIVES

Patients with laboratory criteria for anti-phospholipid syndrome (APS) but presenting only 'non-criteria' clinical manifestations are scarcely characterized in the literature. We aimed to analyse a cohort of these patients regarding the most prevalent manifestations, antibody profile, and treatments, while establishing a comparison with definite APS patients.

METHOD

A retrospective analysis was conducted of individuals fulfilling APS laboratory criteria assessed in two tertiary European hospitals between 2005 and 2020. Patients without clinical criteria but with non-criteria manifestations (termed 'clinical non-criteria') and age-/gender-matched controls were included.

RESULTS

Altogether, 75 clinical non-criteria patients were analysed, with haematological (thrombocytopenia, haemolytic anaemia) and 'mild' neurological manifestations (white-matter lesions, migraine) as the most prevalent non-obstetric involvements. These patients displayed more thrombocytopenia [odds ratio (OR) = 3.6, 95% confidence interval (CI) 1.7-7.6; p = 0.001] than controls with APS, but severe manifestations, such as valvular heart disease (p < 0.001), livedoid vasculopathy, seizures, chorea, transverse myelitis, bone necrosis, and alveolar haemorrhage, occurred only in definite APS patients. Corticosteroids were required by 40% of patients with thrombocytopenia. Manifestations in anticoagulated patients included white-matter lesions, nephropathy, superficial vein thrombosis, amaurosis fugax, and livedoid vasculopathy. Suspicion of progression towards systemic lupus erythematosus (SLE) occurred in 19% of non-SLE individuals.

CONCLUSION

'Clinical non-criteria' patients displayed significant treatment use, predominantly haematological involvement, and less severe manifestations than definite APS controls. Some patients may additionally progress to future SLE. The impact of certain manifestations flags them as potential future contributors to classifying individuals as definite APS.

An advanced understanding of the heterogeneous clinical features of "non-criteria" obstetric antiphospholipid syndrome: Two case reports and a literature review

Antiphospholipid syndrome (APS) is an acquired autoimmune disorder characterized by recurrent venous and/or arterial thrombosis and/or pregnancy complications, in the presence of elevated antiphospholipid (aPL) antibodies. APS in pregnant women is referred to as "obstetrical" APS (OAPS). The diagnosis of definite OAPS requires the presence of one or more typical clinical criteria and persistent aPL antibodies at least 12 weeks apart. However, the classification criteria for OAPS have generated wide discussion, with a growing impression that certain patients not fully meeting these criteria might be inappropriately excluded from the classification, which is known as "non-criteria" OAPS. We present here two unique cases of potentially lethal "non-criteria" OAPS, complicating severe preeclampsia, fetal growth restriction (FGR), liver rupture, preterm birth, refractory recurrent miscarriages, or even stillbirth. We further share our diagnostic search and analysis, treatment adjustment, and prognosis for this unusual antenatal event. We will also present a short review of an advanced understanding of the pathogenetic mechanisms of this disease, heterogeneous clinical features, and potential significance.

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.

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.

Analysis of Serbian Primary Antiphospholipid Syndrome Patients Confirmed a Strong Association Between Livedo Reticularis and Arterial Thrombosis: A National Cross-Sectional Cohort Study

BACKGROUND

Antiphospholipid syndrome (APS) is characterized by antiphospholipid antibodies (aPLs) associated with thrombosis (arterial and/or venous) and/or obstetrical manifestations. However, various manifestations, which are considered to be noncriteria manifestations, are frequently found in APS.

AIM

The purpose of this study was to evaluate whether noncriteria manifestations may be found more frequently in subjects with thrombotic and/or obstetrical APS ("criteria" manifestations) in a population of patients with primary APS (PAPS). This study presents the results from our national cohort.

PATIENTS AND METHODS

This is a cross-sectional study of 360 PAPS patients. Data regarding the presence of thrombocytopenia, livedo reticularis, chorea, and valvulopathy were analyzed. The aPL analysis included the detection of anticardiolipin antibodies (aCLs: immunoglobulin G [IgG]/IgM), anti-β 2 glycoprotein I (IgG/IgM), and lupus anticoagulant positivity.

RESULTS

In our cohort, livedo reticularis was significantly related to arterial thromboses in the same way as valvular manifestations (valvular vegetations and valvular thickening and dysfunction not related to age) ( p = 0.0001, p = 0.013, respectively). Age was strongly related to all the noncriteria manifestations analyzed. Thrombocytopenia was significantly related to β 2 glycoprotein I IgG and lupus anticoagulant positivity ( p = 0.043, p = 0.030, respectively), as well as to double and triple aPL positivity ( p = 0.041, p = 0.013 respectively). Moreover, in a multivariate model, livedo reticularis was strongly and independently related to arterial thrombosis in our cohort (odds ratio, 2.010; confidence interval, 1.229-3.288; p = 0.005).

CONCLUSION

This cross-sectional analysis of a large cohort of Serbian PAPS patients confirmed a strong relationship between livedo reticularis and arterial thrombosis, suggesting a more cautious approach regarding the presence of noncriteria manifestations, especially livedo reticularis, in APS.

Risk of livedo with antiphospholipid antibodies in patients with systemic lupus erythematosus: A systematic review and meta-analysis

Background

Livedo is a well-known skin condition in patients with systemic lupus erythematosus (SLE) which correspond to small vessels involvement. The influence of antiphospholipid antibodies (aPL) on the occurrence of livedo is controversial. The aim of our study was to estimate the risk of livedo associated with aPL in patients with SLE.

Methods

We conducted a systematic review and meta-analysis of the literature from 1977 to 2021 to estimate the risk of livedo in SLE patients according to different aPL profiles. Data sources were PubMed, Embase, Cochrane Library, hand search, and reference lists of studies. Studies were selected if they included SLE patients with descriptions of the exposure to aPL and the outcome ( livedo). Two independent investigators assessed study eligibility, quality, and extracted patient characteristics from each study as well as exposure (aPL) and outcome ( livedo). Risk estimates were pooled using random effects models and sensitivity analyses. For all stages of the meta-analysis, we followed the PRISMA guidelines. PROSPERO registration number: CRD42015027377.

Results

Of the 2,355 articles identified, 27 were included with a total of 4,810 SLE patients. The frequency of livedo was 25.5% in aPL-positive patients and 13.3% in aPL-negative patients. The overall Odds Ratio (OR) for livedo in aPL-positive patients compared to aPL-negative patients was 2.91 (95% CI; 2.17–3.90). The risk of livedo was significantly increased for most of aPL subtypes, including lupus anticoagulant (LA) (OR = 4.45 [95% CI; 2.21–8.94]), IgG anticardiolipin (OR = 3.95 [95% CI; 2.34–6.65]), and IgG anti-β2-glycoprotein 1 (OR = 3.49 [95% CI; 1.68–7.27]).

Conclusions

We demonstrated in this meta-analysis an excess risk of livedo in aPL-positive SLE patients compared to aPL-negative patients. For daily practice, in patients with SLE, livedo associated with aPL could correspond to a peculiar group of patients with small vessel disease. Livedo could be a good candidate for inclusion in future classification criteria for antiphospholipid syndrome.

IgA Antiphospholipid Antibodies in Antiphospholipid Syndrome and Systemic Lupus Erythematosus

Objective: To define the role of IgA antibodies to cardiolipin (aCL) and IgA antibodies to beta-2 glycoprotein 1 (anti-β2-GP1) in the development of vascular complications in patients with antiphospholipid syndrome (APS) and systemic lupus erythematosus (SLE). Material and methods: A total of 187 patients with one of the following diagnoses: primary APS (PAPS), probable APS, SLE with APS, and SLE without APS. The comparison group consisted of 49 patients with other rheumatic diseases (RD), the control group included 100 relatively healthy individuals (without RD, oncological pathology, and infectious diseases). All patients underwent standard clinical, laboratory, and instrumental examinations before being included in the study and during follow-up. The aPL study included the determination of IgG/IgM aCL, IgG/IgM anti-β2-GP1 by enzyme-linked immunosorbent assay (ELISA), IgG/IgM/IgA aCL, IgG/IgM/IgA anti-β2-GP1 by chemiluminescence analysis (CLA), and lupus anticoagulant (LA). Results: IgA aCL were detected in 75 (40%) of the 187 patients with APS and SLE, in none of the comparison group, and in 2 (2%) of the control one. IgA anti-β2-GP1 were detected in 63 (34%) of the 187 patients with APS and SLE, in none of the patients in the comparison group, and in one (1%) of the control group. The prevalence of IgA aCL and IgA anti-β2-GP1 and their levels were statistically significantly higher in patients with APS (PAPS and SLE + APS) than the levels in patients with SLE and those of the comparison and control groups (p < 0.05). IgA aCL and IgA anti-β2-GP1 were significantly associated with thrombosis in APS (χ2 = 4.96; p = 0.02 and χ2 = 4.37; p = 0.04, respectively). The risk of thrombosis was 2.04 times higher in patients with positive IgA aCL than in patients without these antibodies, as well as in patients with positive IgA anti-β2-GP1; it was twice as high as in patients without antibodies. There was a high specificity of IgA aCL and IgA anti-β2-GP1 for both the diagnosis of APS and its clinical manifestations, despite a low sensitivity. Conclusions: The study revealed a relationship of thrombosis and APS with IgA aCL and IgA anti-β2-GP1. There was a high specificity of IgA aCL and IgA anti-β2-GP1 (95% and 93%, respectively) for the diagnosis of APS with a low sensitivity (54% and 44%, respectively). There were no patients with isolated positivity of IgA aCL and IgA anti-β2-GP1.

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.

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.

Non-criteria manifestations in primary antiphospholipid syndrome: a French multicenter retrospective cohort study

Background

From this retrospective study, we aimed to (1) describe the prevalence and characteristics of non-criteria features in primary antiphospholipid syndrome (p-APS) and (2) determine their prognostic value.

Methods

This retrospective French multicenter cohort study included all patients diagnosed with p-APS (Sydney criteria) between January 2012 and January 2019. We used Kaplan-Meier and adjusted Cox proportional hazards models to compare the incidence of relapse in p-APS with and without non-criteria manifestations.

Results

One hundred and seventy-nine patients with p-APS were included during the study time, with a median age of 52.50 years [39.0; 65.25] and mainly women (n = 112; 62.6%). Among them, forty-three patients (24.0%) presented at least one non-criteria manifestation during the follow-up: autoimmune cytopenias (n = 17; 39.5%), Libman Sachs endocarditis (n = 5; 11.6%), APS nephropathy (n = 4; 9.3%), livedo reticularis (n = 8; 18.6%), and neurological manifestations (n = 12; 27.9%). In comparison to p-APS without any non-criteria manifestations (n = 136), p-APS with non-criteria features had more arterial thrombosis (n = 24; 55.8% vs n = 48; 35.3%; p = 0.027) and more frequent pre-eclampsia (n = 6; 14.3% vs n = 4; 3.1%; p = 0.02). The prevalence of triple positivity was significantly increased in patients with non-criteria features (n = 20; 47.6% vs n = 25; 19.8%; p = 0.001). Patients with p-APS and non-criteria manifestations (n = 43) received significantly more additional therapies combined with vitamin K antagonists and/or antiaggregants. Catastrophic APS (CAPS) tended to be more frequent in p-APS with non-criteria features (n = 2; 5.1% vs none; p = 0.074).

The p-APS with non-criteria manifestations had significantly increased rates of relapse (n = 20; 58.8% vs 33; 33.7%; p = 0.018) in bivariate analysis, but in survival analyses, the hazard ratio (HR) of relapse was not significantly different between the two groups (HR at 1.34 [0.67; 2.68]; p = 0.40).

Conclusions

The presence of non-criteria features is important to consider, as they are associated with particular clinical and laboratory profiles, increased risk of relapse, and need for additional therapies. Prospective studies are necessary to better stratify the prognosis and the management of p-APS.

An Update on Antiphospholipid Syndrome

PURPOSE OF REVIEW

To review the recent available evidence on epidemiology, pathogenesis, clinical phenotypes, and management of antiphospholipid syndrome (APS) and summarize potential future research perspectives.

RECENT FINDINGS

Accumulating evidence has further expanded our understanding of the disease, including new data about the incidence and prevalence of APS, novel pathways supporting the role of thrombo-inflammation in APS including platelet, monocyte and endothelial cell activation, pro-inflammatory cytokine and chemokine production, complement activation, neutrophil extracellular trap release, and type I interferon gene expression that could yield to new potential treatment targets, better identification of criteria and non-criteria clinical phenotypes, antiphospholipid antibody profiles and their associations with clinical outcomes, prognostic tools, and treatment strategies based on recent evidence-based recommendations for patients with thrombotic and obstetric APS, with or without systemic lupus erythematosus. Ongoing research efforts and international collaborations enhance our knowledge of this rare and often devastating syndrome and help improve patient care and health outcomes.

The presence of non-criteria manifestations negatively affects the prognosis of seronegative antiphospholipid syndrome patients: a multicenter study

Background

Seronegative antiphospholipid syndrome (SN-APS) is often defined as the presence of APS criteria manifestations, negative antiphospholipid antibodies (aPL), and coexistence of APS non-criteria manifestations. Nevertheless, the impact of these non-criteria features is still unclear. On a different note, the relevance of one single aPL positive determination in patients with APS manifestations is another domain with limited evidence. We aim to compare the course of SN-APS and single-positive aPL (SP-aPL) patients with that of individuals with APS manifestations without non-criteria features/aPL positivity (controls).

Methods

Retrospective analysis of patients with thrombosis/obstetric morbidity assessed in two European hospitals between 2005 and 2020. Patients were divided into SN-APS, SP-aPL, and control groups. Clinical characteristics, comorbidities, and therapies were compared.

Results

A total of 82 patients were included in the SN-APS group, 88 in the SP-aPL group, and 185 in the control group. In Cox regression model, SN-APS displayed more thrombosis recurrence than controls (HR 3.8, 95% CI 2.2–6.5, p < 0.001) even when adjusting for the presence of hereditary thrombophilia, systemic lupus erythematosus, or contraceptive hormonal treatment. In SP-aPL, the difference in thrombosis recurrence did not reach statistical significance (p = 0.078). Indefinite anticoagulation (p < 0.001 and p = 0.008, respectively) and vitamin K antagonist (VKA) use (p < 0.001 in both cases) were more common in SN-APS/SP-aPL.

Conclusion

SN-APS displayed more thrombosis recurrence, indefinite anticoagulation, and VKA use than controls without non-criteria manifestations. The presence of such features in patients with thrombosis and negative aPL may negatively impact their clinical course.

Does Adjusted Global Antiphospholipid Syndrome Score (aGAPSS) Predict the Obstetric Outcome in Antiphospholipid Antibody Carriers? A Single-Center Study

The adjusted Global Antiphospholipid Syndrome (APS) Score (aGAPSS) is a tool proposed to quantify the risk for antiphospholipid antibody (aPL)-related clinical manifestations. However, aGAPSS has been validated mainly for thrombotic events and studies on APS-related obstetric manifestations are scarce. Furthermore, the majority of them included patients with positive aPL and different autoimmune diseases. Here, we assess the utility of aGAPSS to predict the response to treatment in aPL carriers without other autoimmune disorders. One-hundred and thirty-seven women with aPL ever pregnant were included. Sixty-five meet the APS classification criteria, 61 had APS-related obstetric manifestations, and 11 were asymptomatic carriers. The patients' aGAPSS risk was grouped as low (< 6, N = 73), medium (6-11, N = 40), and high risk (≥ 12, N = 24). Since vascular risk factors included in the aGAPSS were infrequent in this population (< 10%), the aGAPSS score was mainly determined by the aPL profile. Overall, the live birth rate was 75%, and 37.2% of the patients had at least one adverse pregnancy outcome (APO). When considering patients according to the aGAPSS (high, medium, and low risk), no significant differences were found for pregnancy loss (29.2%, 25%, and 21.9%) or APO (33.3%, 47.5%, and 32.9%). In the present study, including aPL carriers without other autoimmune diseases, aGAPSS is not a valuable tool to identify patients at risk for obstetric complications despite treatment. In these patients with gestational desire, in addition to the aPL profile, other pregnancy-specific factors, such as age or previous obstetric history, should be considered.

Severe digital ischemia coexists with thrombocytopenia in malignancy-associated antiphospholipid syndrome: A case report and review of literature

BACKGROUND

Paraneoplastic syndromes are characterized by atypical clinical manifestations. Several reports of hepatocellular carcinoma (HCC) paraneoplastic phenomena have been reported. They usually manifest as one type in an individual, but it is not common for the two clinical manifestations to occur simultaneously.

CASE SUMMARY

A 52-year-old female patient was admitted to hospital with pale skin and numbness of the second to fifth fingers in the left hand, which rapidly developed into severe digital ischemia. Computed tomography angiography revealed uneven thickness of the left ulnar artery with severe local luminal stenosis. Blood analysis during hospitalization showed persistent mild to medium thrombocytopenia and insensitive to hormonal therapy. Antiphospholipid antibody testing showed high titer of IgG anticardiolipin antibodies (aCLs), IgA aCLs, IgG anti-β2-glycoprotein-I (anti-β2 GPI), and IgA anti-β2 GPI. The exact diagnosis was HCC when the high a-fetoprotein levels, computed tomography findings, and the history of chronic hepatitis B came together. This was a rare case of coexisting manifestations as presenting symptoms of malignancy-associated antiphospholipid syndrome. The patient underwent several operations, antithrombotic treatments and hormonal therapy. However, the patient refused chemotherapy and died 8 wk after diagnosis.

CONCLUSION

This report highlights the importance of atypical clinical changes that could alert the physicians to vigilance for a concomitant underlying malignancy.

A catastrophic seronegative anti-phospholipid syndrome: case and literature review

Background

Antiphospholipid Syndrome (APS) is a multisystemic autoimmune disease characterized by arterial and venous thrombosis and / or obstetric morbidity in the presence of at least one circulating anti-phospholipid antibody. The spectrum of vascular events varies from deep venous thrombosis to catastrophic APS, a rare form characterized by acute multiorgan thrombosis and high mortality.

Case report

We present the case of a 32-week pregnant woman arriving in the hospital emergency room with bilateral acute lower limb ischemia. In the obstetric evaluation, fetal death was declared. Computerized Tomography angiography showed pulmonary embolism of both pulmonary arteries, areas of splenic and right renal infarction and multiple arterial and venous thrombosis. The patient underwent urgent caesarean section and axillary-bifemoral bypass. No events registered. In the postoperative period, in an intensive care unit, treatment with rituximab and plasmapheresis were added to anticoagulant therapy. The laboratorial investigation was negative for thrombophilia and autoimmune diseases.

Conclusion

Catastrophic APS develops quickly, with multiorgan involvement and high mortality rate. The presented case poses a multidisciplinary challenge, with the surgical approach of extra-anatomical revascularization being less invasive and guaranteeing immediate perfusion of the lower limbs. Although the serological tests were negative for anti-phospholipid antibodies, this case hardly fits into another diagnosis. Therefore, it was treated as a catastrophic APS, having shown a favorable evolution.

Role of antiphospholipid antibodies in the diagnosis of antiphospholipid syndrome

The diagnosis of antiphospholipid syndrome (APS) relies on the detection of antiphospholipid antibodies (aPL). Currently, lupus anticoagulant (LA), anticardiolipin (aCL), and antibeta2-glycoprotein I antibodies (aβ2GPI) IgG or IgM are included as laboratory criteria, if persistently present. LAC measurement remains a complicated procedure with many pitfalls and interfered by anticoagulant therapy. Solid-phase assays for aCL and aβ2GPI show interassay differences. These methodological issues make the laboratory diagnosis of APS challenging. In the interpretation of aPL results, antibody profiles help in identifying patients at risk. Other aPL, such as antibodies against the domain I of beta2-glycoprotein (aDI) and antiphosphatidylserine-prothrombin (aPS/PT) antibodies have been studied in the last years and may be useful in risk stratification of APS patients. Because of the methodological shortcomings of immunological and clotting assays, these non-criteria aPL may be useful in patients with incomplete antibody profiles to confirm or exclude the increased risk profile. This manuscript will focus on the laboratory aspects, the clinical relevance of assays and interpretation of aPL results in the diagnosis of APS.

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The presence of antiphospholipid antibodies (aPL) define the diagnosis of the antiphospholipid syndrome (APS).

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Laboratory criteria are lupus anticoagulant, anticardiolipin (aCL), and antibeta2-glycoprotein I antibodies (aβ2GPI) IgG/IgM.

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Lupus anticoagulant measurement, as well as solid phase assays for aCL and aβ2GPI, show methodological challenges.

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Antibodies against domain I of β2GPI (aDI) and antiphosphatidylserine-prothrombin (aPS/PT) antibodies are non-criteria aPL.

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aDI and aPS/PT may be useful in risk stratification of APS patients.

Presence of Extra-Criteria Antiphospholipid Antibodies Is an Independent Risk Factor for Ischemic Stroke

Background: Ischemic stroke is the most common and severe arterial thrombotic event in Antiphospholipid syndrome (APS). APS is an autoimmune disease characterized by the presence of thrombosis and antiphospholipid antibodies (aPL), which provide a pro-coagulant state. The aPL included in the classification criteria are lupus anticoagulant, anti-cardiolipin (aCL) and anti-β2-glycoprotein-I antibodies (aB2GPI) of IgG and IgM isotypes. Extra-criteria aPL, especially IgA aB2GPI and IgG/IgM anti-phosphatidylserine/prothrombin antibodies (aPS/PT), have been strongly associated with thrombosis. However, their role in the general population suffering from stroke is unknown. We aim (1) to evaluate the aPL prevalence in ischemic stroke patients, (2) to determine the role of aPL as a risk factor for stroke, and (3) to create an easy-to-use tool to stratify the risk of ischemic stroke occurrence considering the presence of aPL and other risk factors.

Materials and Methods: A cohort of 245 consecutive ischemic stroke patients was evaluated in the first 24 h after the acute event for the presence of classic aPL, extra-criteria aPL (IgA aB2GPI, IgG, and IgM aPS/PT) and conventional cardiovascular risk factors. These patients were followed-up for 2-years. A group of 121 healthy volunteers of the same age range and representative of the general population was used as reference population. The study was approved by the Ethics Committee for Clinical Research (Reference numbers CEIC-14/354 and CEIC-18/182).

Results: The overall aPL prevalence in stroke patients was 28% and IgA aB2GPI were the most prevalent (20%). In the multivariant analysis, the presence of IgA aB2GPI (OR 2.40, 95% CI: 1.03–5.53), dyslipidemia (OR 1.70, 95% CI: 1.01–2.84), arterial hypertension (OR 1.82, 95% CI: 1.03–3.22), atrial fibrillation (OR 4.31, 95% CI: 1.90–9.78), and active smoking (OR 3.47, 95% CI: 1.72–6.99) were identified as independent risk factors for ischemic stroke. A risk stratification tool for stroke was created based on these factors (AUC: 0.75).

Conclusions: IgA aB2GPI are an important independent risk factor for ischemic stroke. Evaluation of aPL (including extra-criteria) in cardiovascular risk factor assessment for stroke can potentially increase the identification of patients at risk of thrombotic event, facilitating a decision on preventive treatments.

B cells in primary antiphospholipid syndrome: Review and remaining challenges

It is now widely accepted that antiphospholipid antibodies (aPL) have direct pathogenic effects and that B cells, notably through aPL production, play a key role in the development of antiphospholipid syndrome (APS). Recent findings strengthened the implication of B cells with the description of specific B cell phenotype abnormalities and inborn errors of immunity involving B cell signaling in APS patients. In addition, it has been shown in preclinical models that cross-reactivity between APS autoantigens and mimotopes expressed by human gut commensals can lead to B cell tolerance breakdown and are sufficient for APS development. However, B cell targeting therapies are surprisingly not as effective as expected in APS compared to other autoimmune diseases. Elucidation of the B cell tolerance breakdown mechanisms in APS patients may help to develop and guide the use of novel therapeutic agents that target B cells or specific immune pathway.

The impact of various entities of antiphospholipid antibodies positivity on adverse pregnancy outcome. An epidemiological perspective

The aim of the study was to evaluate the rate of obstetric complications and the burden of obstetric outcomes in antiphospholipid syndrome (APS), non-criteria APS and asymptomatic antiphospholipid antibodies (aPL) carriers. From 2013-2018, 163 pregnant subjects with aPL antibodies and 785 controls were enrolled. Penalized logistic regression was used to compare obstetric complications. Cases included 62 complete APS (38 %), 48 non-criteria APS (29.4 %) and 53 (32.5 %) asymptomatic aPL-carriers. Connective tissue diseases (CTDs) were diagnosed in 31.3 % of cases. The rate of high-risk aPL profile was higher (p < .01) in APS (67.7 %) compared to non-criteria (14.6 %) and aPL-carriers (9.4 %). Double/triple positivity was 33.9 % (p < .05 compared to non-criteria and aPL-carriers) in APS, 10.4 % in non-criteria and 9.4 % in aPL-carriers. The rate of adverse pregnancy outcomes were 5.6 % in controls, 41.9 % (adj.OR = 6.95 %CI = 2.7-13.5) in APS, 25 % (adj.OR = 4.4,95 %CI = 2-9.4) in non-criteria and 28.3 % (OR = 4.95 %CI = 1.8-8.8) in aPL-carriers. CTDs were independently associated with an increased risk of adverse obstetric outcomes (OR = 2.8,95 %CI = 1.36-5.89). The attributable fraction (AF) of adverse obstetric events was higher among low-risk antibodies compared to high-risk (AF = 0.27,95 %CI = 0.22-0.31 vs AF = 0.16,95 %CI = 0.16-0.2,p < .01) and among single positivity compared to double/triple positivity (AF = 0.32,95 %CI = 0.26-0.37 vs AF = 0.11,95 %CI = 0.09-0.13,p < .01) suggesting that low-risk subjects are responsible for a high burden of obstetric complications.