Novel diagnostic and therapeutic frontiers in thrombotic anti-phospholipid syndrome

Biological therapy in systemic lupus erythematosus, antiphospholipid syndrome, and Sjögren's syndrome: evidence- and practice-based guidance

Systemic lupus erythematosus (SLE), antiphospholipid syndrome (APS), and Sjögren's syndrome (SS) are heterogeneous autoimmune diseases. Severe manifestations and refractory/intolerance to conventional immunosuppressants demand other options, namely biological drugs, and small molecules. We aimed to define evidence and practice-based guidance for the off-label use of biologics in SLE, APS, and SS. Recommendations were made by an independent expert panel, following a comprehensive literature review and two consensus rounds. The panel included 17 internal medicine experts with recognized practice in autoimmune disease management. The literature review was systematic from 2014 until 2019 and later updated by cross-reference checking and experts' input until 2021. Preliminary recommendations were drafted by working groups for each disease. A revision meeting with all experts anticipated the consensus meeting held in June 2021. All experts voted (agree, disagree, neither agree nor disagree) during two rounds, and recommendations with at least 75% agreement were approved. A total of 32 final recommendations (20 for SLE treatment, 5 for APS, and 7 for SS) were approved by the experts. These recommendations consider organ involvement, manifestations, severity, and response to previous treatments. In these three autoimmune diseases, most recommendations refer to rituximab, which aligns with the higher number of studies and clinical experience with this biological agent. Belimumab sequential treatment after rituximab may also be used in severe cases of SLE and SS. Second-line therapy with baricitinib, bortezomib, eculizumab, secukinumab, or tocilizumab can be considered in SLE-specific manifestations. These evidence and practice-based recommendations may support treatment decision and, ultimately, improve the outcome of patients living with SLE, APS, or SS.

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.

Antiphospholipid Antibodies and Lipids in Hematological Malignancies

One of the main groups of lipids is phospholipids, which are mainly involved in forming cell membranes. Neoplastic processes such as cell replication have increased lipid synthesis, making tumor cells dependent on this synthesis to maintain their requirements. Antiphospholipid antibodies attack phospholipids in the cell membranes. Three main types of antiphospholipid antibodies are recognized: anti-β2 glycoprotein I (anti-β2GP-I), anticardiolipin (aCL), and lupus anticoagulant (LA). These types of antibodies have been proven to be present in hematological neoplasms, particularly in LH and NHL. This review on antiphospholipid antibodies in hematological neoplasms describes their clinical relationship as future implications at the prognostic level for survival and even treatment.

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.

Biochemical and clinical predictors in pregnant women with antiphospholipid syndrome and systemic lupus erythematosus: comprehensive update

BACKGROUND

Autoimmune diseases as antiphospholipid syndrome (APS) and systemic lupus erythematosus (SLE) could cause many maternal complications. The most common maternal complications of autoimmune diseases are lupus flare, hypertension, nephritis, preeclampsia (PE), eclampsia, and poor pregnancy outcomes which including preterm delivery and pregnancy loss. Only the lupus anticoagulant in the greatest prospective multicenter study has been associated with adverse pregnancy outcomes of the APS.

PURPOSE

This review aims to provide a comprehensive update for predictors in pregnant women with APS/SLE.

METHODS

These data have been collected from clinical and pathological studies, systematic reviews, and meta-analysis.

RESULTS

In recent years the SLE and APS demonstrated to have different and valuable clinical and biomarker predictors for the pregnancy outcome. Treatment of pregnant women with APS is low molecular weight heparin (LMWH) and aspirin; however, around 75% of this management is considered successful.

CONCLUSION

This review summarizes recent research that focuses on biochemical and clinical predictors of adverse pregnancy outcomes (APOs) of pregnant women with SLE and APS. Furthermore, we have collected more evidence that confirms the safety and efficacy of hydroxychloroquine (HCQ) preventing APOs.

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.

Avidity of anti-phospholipid antibodies in relation to their levels

Introduction

The heterogeneity of anti-phospholipid antibodies can be manifested not only in different antigenic specificities, but also in their avidities. The aim of the study was to investigate the relationship between anti-cardiolipin antibody (aCL) IgG avidities and levels within the range of their titres, from very low to high ones.

Material and methods

We analyzed 78 serum samples from 60 patients by ELISA with chaotropic agents, using urea concentration of 6 and 8 mol/l and single diluted serum samples. The changes of aCL levels and avidities were explored during a long-term follow-up in 14 patients.

Results

The avidities of aCLs did not differ in the groups of patients classified according to aCL levels. The higher avidity antibodies predominated in our patients and the fluctuation of avidities in the longitudinal follow-up did not show significant differences. No relationship between aCL levels and their avidities was found.

Conclusions

aCL avidities seem to have no relationship with aCL levels and high-avidity aCLs; the potentially deleterious effects might be present also in patients with low and extremely low aCL levels. Avidity of aCLs belongs to stable characteristics with insignificant changes in time.

Obstetric antiphospholipid syndrome is not associated with an increased risk of subclinical atherosclerosis

OBJECTIVES

The persistent positivity of aPLs, either isolated or associated with thrombotic and/or obstetric events (APS), has been associated with the increase of intima-media thickness (IMT) and carotid plaques. Despite the fact that aPLs can promote both thrombotic and obstetric complications, some pathogenic differences have been documented between the two entities. This study aimed to evaluate whether the atherosclerotic risk differs between subjects with obstetric and thrombotic APS.

METHODS

A total of 167 APS women (36 obstetric and 131 thrombotic) were compared with 250 aPLs negative controls. IMT of the common carotid artery (CCA) and of the bulb and the prevalence of carotid plaques were assessed.

RESULTS

CCA- and bulb-IMT were significantly higher in women with thrombotic APS, while being similar between the obstetric APS and the controls [CCA-IMT: mean (s.d.) 0.97 (0.49), 0.78 (0.22) and 0.81 (0.12) mm for the thrombotic, obstetric and control groups, respectively, P < 0.001 between thrombotic and controls, P = 0.002 between thrombotic and obstetric; bulb-IMT: mean (s.d.) 1.38 (0.79), 0.96 (0.27) and 0.96 (0.51) mm for the thrombotic, obstetric and control groups, P < 0.001]. Women with thrombotic APS had significantly increased risk of presenting carotid plaques. This risk was significantly lower in obstetric APS.

CONCLUSION

Unlike thrombotic APS, obstetric APS is not associated with an increase of markers of subclinical atherosclerosis. If confirmed on wider populations, these results could suggest different pathogenetic role of aPLs in promoting atherosclerosis in vascular and obstetric APS, and raise questions on the risk-benefit profile of thromboprophylaxis in obstetric APS outside pregnancy periods.

"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.

Pregnancy success rate and response to heparins and/or aspirin differ in women with antiphospholipid antibodies according to their Global AntiphosPholipid Syndrome Score

BACKGROUND

The current treatment to prevent pregnancy morbidity (PM) associated with antiphospholipid antibodies (aPL) is based on the use of low dose aspirin and low molecular weight heparin (henceforth defined as standard of care (SoC) treatment). Despite the SoC, up to 30% of women with aPL continue to have pregnancy complications. The global antiphospholipid syndrome (APS) score (GAPSS) is a tool to quantify the risk for the aPL-related clinical manifestations. In this study, we investigated the individual clinical response to SoC in women with aPL after stratifying them according to their GAPSS.

METHODS

One-hundred-fourty-three women (352 pregnancies) with aPL ever pregnant treated with SoC therapy were included. The patients GAPSS was then grouped according to the patients' GAPSS into low risk (< 6), medium risk (6-11), and high risk (≥12).

RESULTS

The live birth rate was 70.5% (248 out of the 352 pregnancies), 45 patients (31%) experienced at least one event of PM, defined as early or late. Patients were stratified according to GAPSS values, in order to identify a low risk group (GAPSS <6, n = 72), a medium risk group (GAPSS 6-11, n = 66) and a high risk group (GAPSS ≥12, n = 5). When considering patients who ever experienced any PM while treated with SoC, all patients in the high risk group experienced PM, while patients in the medium group had a significant higher rate of PM when compared to the low risk group [29 (43.9%) patients V.s. 11 (15.3%), respectively; p < 0.001]. When analysing the number of pregnancies in the three groups, patients in the high risk group had significantly lower live birth rates, when compared to the other groups [11 (40.7%) live births vs. 100 (62.1%) and 137 (82.5%), respectively; p < 0.05]. Furthermore, patients with medium risk group also had significantly lower live birth rates, when compared to the lower risk group (p < 0.001).

CONCLUSIONS

GAPSS might be a valuable tool for to identify patients with a higher likelihood of response to SoC.

Reliability of Lupus Anticoagulant and Anti-phosphatidylserine/prothrombin Autoantibodies in Antiphospholipid Syndrome: A Multicenter Study

Background: Is it well-known that one of the major drawbacks of Lupus Anticoagulant (LA) test is their sensitivity to anticoagulant therapy, due to the coagulation based principle. In this study we aimed to assess the reproducibility of LA testing and to evaluate the performance of solid assay phosphatidylserine/prothrombin (aPS/PT) antibodies.

Methods: We included 60 patients that fulfilled the following inclusion criteria: (I) diagnosis of thrombotic antiphospholipid syndrome (APS); (II) patients with thrombosis and (a) inconstant previous LA positivity and/or (b) positivity for antiphospholipid antibodies (aPL) at low-medium titers [defined as levels of anti-β2Glycoprotein-I or anticardiolipin (IgG/IgM) 10–30 GPL/MPL] with no previous evidence of LA positivity. aPL testing was performed blindly in 4 centers undertaking periodic external quality assessment.

Results: The 60 patients enrolled were distributed as follows: 43 (71.7%) with thrombotic APS, 7 (11.7%) with thrombosis and inconstant LA positivity and 10 (16.7%) with low-medium aPL titers. Categorical agreement for LA among the centers ranged from 0.41 to 0.60 (Cohen's kappa coefficient; moderate agreement). The correlation determined at the 4 sites for aPS/PT was strong, both quantitatively (Spearman rho 0.84) and when dichotomized (Cohen's kappa coefficients = 0.81 to 1.0). Discordant (as defined by lack of agreement in ≥3 laboratories) or inconclusive LA results were observed in 27/60 (45%) cases; when limiting the analysis to those receiving vitamin K antagonist (VKA), the level of discordant LA results was as high as 75%(15/20). Conversely, aPS/PT testing showed an overall agreement of 83% (up to 90% in patients receiving VKA), providing an overall increase in test reproducibility of +28% when compared to LA, becoming even more evident (+65%) when analyzing patients on VKA. In patients treated with VKA, we observed a good correlation for aPS/PT IgG testing (Cohen's kappa coefficients = 0.81–1; Spearman rho 0.86).

Conclusion: Despite the progress in the standardization of aPL testing, we observed up to 45% of overall discrepant results for LA, even higher in patients on VKA. The introduction of aPS/PT testing might represent a further diagnostic tool, especially when LA testing is not available or the results are uncertain.

The association of adjusted Global AntiphosPholipid Syndrome Score (aGAPSS) with cardiovascular disease in subjects with antiphospholipid antibodies

BACKGROUND AND AIMS

Cardiovascular disease (CVD), including coronary artery disease and stroke/peripheral artery disease, is less commonly reported than venous thromboembolism in subjects with antiphospholipid antibodies (aPLs) and little is known about the association of CVD with adjusted Global AntiphosPholipid Syndrome Score (aGAPSS).

METHODS

Consecutive aPLs subjects were enrolled to assess the association of CVD with aGAPSS. Moreover, additional risk factors of CVD were identified by means of multivariate analysis to design an aGAPSS specific for CVD (aGAPSS_CVD).

RESULTS

A total of 192 aPLs subjects (34 males, 158 females, mean age 49.84 ± 12.0 years) were enrolled. CVD was reported in 52 subjects (27.1%), 26 episodes of coronary artery disease and 26 stroke/peripheral artery disease. The prevalence of CVD increased for increasing aGAPSS ranging from 20.5% in the lowest aGAPSS category, up to 37.9% in the highest category (p = 0.027). ROC analysis showed that aGAPSS detected 63.0% of CVD and was associated with OR for CVD of 2.52 (95%CI: 1.24-5.10, p = 0.010). When including obesity, diabetes and smoking habit in the score, we found that aGAPSSCVD detected 71.4% of CVD (72.4% for early-CVD and 69.0% for CVD after 50 years) with an OR for CVD of 4.68 (95%CI: 2.31-9.51, p < 0.001).

CONCLUSIONS

The aGAPSS_CVD, obtained after adding obesity, smoking habit and diabetes to the standard aGAPSS, showed a higher detection rate of CVD in aPLs subjects, particularly of early-CVD. These results need to be validated in ad hoc designed prospective studies.

Subclinical atherosclerosis in asymptomatic carriers of persistent antiphospholipid antibodies positivity: A cross-sectional study

BACKGROUND

Whereas the relationship between subclinical atherosclerosis and antiphospholipid syndrome (APS) has been widely investigated, little is known about subclinical atherosclerosis in asymptomatic carriers with isolated antiphospholipid antibodies positivity (APP).

METHODS

Consecutive APP carriers, APS subjects and matched controls were enrolled. Intima-media thickness of the common carotid artery (CCA-IMT) and of the Bulb (Bulb-IMT) and the prevalence of carotid plaques were assessed in all enrolled subjects.

RESULTS

A total of 104 APP carriers, 221 APS subjects, and 325 matched controls were recruited. As compared with controls, APP carriers and APS subjects showed a higher CCA-IMT (0.90 ± 0.24 vs 0.82 ± 0.12, p = 0.014 and 0.93 ± 0.42 vs 0.82 ± 0.12, p < 0.001, respectively), Bulb-IMT (1.10 ± 0.44 vs 0.95 ± 0.18, p = 0.006 and 1.22 ± 0.68 vs 0.95 ± 0.18, p < 0.001, respectively) and an increased prevalence of carotid plaques (33.7% vs 10.2%, p < 0.001 and 38.5% vs 10.2%, p < 0.001, respectively). These results were confirmed stratifying for antibody isotype, after excluding subjects with systemic lupus erythematosus or other autoimmune diseases and after adjusting for major clinical and demographic variables. CCA-IMT, Bulb-IMT and the prevalence of carotid plaques were higher in subjects with high-titer antibodies and progressively increased for an increasing number of positive antibodies.

CONCLUSIONS

Similar to APS subjects, APP carriers have enhanced subclinical atherosclerosis, a more severe disease being observed in the presence of high-titer antibodies and multiple antibodies positivity. These data argue for a strict monitoring of subclinical signs of atherosclerosis and of cardiovascular risk factors in asymptomatic APP carriers.

Can we withdraw anticoagulation in patients with antiphospholipid syndrome after seroconvertion?

The current mainstay of treatment in patients with thrombotic antiphospholipid syndrome (APS) is long-term anticoagulation, mainly with Vitamin K antagonist agents. Some recently available studies have created new ground for discussion about the possible discontinuation of anticoagulation therapy in patients with a history of thrombotic APS in whom antiphospholipid antibodies (aPL) are not detected any longer (i.e. aPL seroconversion). We report the main points discussed at the last CORA Meeting regarding the issue whether or not anticoagulation can be stopped after aPL seroconversion. In particular, we systematically reviewed the available evidence investigating the clinical outcome of APS patients with aPL seroconversion in whom anticoagulation was stopped when compared to those in whom therapy was continued regardless the aPL profile. Furthermore, the molecular basis for the aPL pathogenicity, the available evidence of non-criteria aPL and their association with thrombosis are addressed. To date, available evidence is still limited to support the indication to stop oral anticoagulation therapy in patients with a previous diagnosis of thrombotic APS who subsequently developed a negative aPL profile. The identification of the whole risk profile for cardiovascular manifestations and possibly of a second level aPL testing in selected patients with aPL might support the eventual clinical decision but further investigation is warranted.