Antiphospholipid Antibody Syndrome Patients Research Articles

Anti-phosphatidyl-serine/prothrombin (aPS/PT) antibodies are superior predictors of LAC presence and APS diagnoses: A single center study

Background and aimsSeveral non-criteria (NC) anti-phospholipid antibodies (APLA) have been proposed as candidates for antiphospholipid antibody syndrome (APS) diagnosis. The objectives of this study were 1) to determine the association of five different NC-APLA with positivity for Lupus anti-coagulant (LAC) and the criteria antibodies anti-cardiolipin (aCL) and anti-beta glycoprotein (aB2GPI), and 2) to assess the ability of NC-APLA to predict LAC presence and clinical APS diagnoses. Material and methodsResults from 486 patients tested for LAC and APLA were retrieved. Patients were grouped according to LAC and serology positivity into three groups: Single-positives (SP) for LAC, aCL or aB2GPI; Double-positives for aCL and aB2GPI; Triple-positives (TP) for LAC, aCL and aB2GPI. NC-ALPA titers were compared between LAC-positive and negative and APS and non-APS patients. ResultsForty-two of 486 patients were LAC-positive and 28 were diagnosed with APS. All criteria and NC-APLA titers were significantly higher in TP than SP patients. ROC analyses based on LAC status showed highest area under the curve (AUC, 95% CI) for aPS/PT IgG (0.75, 0.65–0.85) and aPS/PT IgM (0.73, 0.63–0.82). Based on APS diagnosis, aPS/PT IgM achieved highest AUC (0.87; 0.79–0.95). ConclusionAnti-phosphatidyl-serine/prothrombin (aPS/PT) antibodies are superior predictors of LAC presence and APS diagnoses.

Antiphospholipid Antibody Syndrome (APS) Pediatric Patient Outcomes on Warfarin

Background: Antiphospholipid antibody syndrome (APS) is an acquired thromboembolism (TE) risk factor and places patients at very high risk of recurrent TE. APS diagnosis requires venous (deep vein thrombosis (DVT) or pulmonary embolism (PE)) or arterial thromboembolism and laboratory diagnosis including persistently positive lupus anticoagulant (LA) or elevated anticardiolipin (aCL) and/or beta 2 glycoprotein I (B2GPI) antibodies tested 12 weeks apart. Vitamin K antagonist (warfarin) is the standard of care anticoagulant to reduce risk of TE recurrence in APS patients. Warfarin is dosed based on the International Normalized Ratio (INR) with established therapeutic ranges for optimal efficacy and safety. The reported time in therapeutic range (TTR) varies greatly across specialties with an average TTR of 50-55%. However, it is often difficult to maintain target INR in APS. Furthermore, there is limited data evaluating pediatric patients with APS and their TTR on warfarin and outcomes. Aim: To evaluate the relationship of APS status to TTR and outcomes of patients < 21 years of age with APS who are on warfarin anticoagulation. Methods: This was a single center analysis of APS patients between July 2019 and May 2022 who were enrolled in a multi-center prospective study of pediatric patients on warfarin therapy, eKITE (electronic KidClot Thrombophilia Education). The study included an online learning series regarding warfarin management. Home INR meters and test strips were provided to all patients to perform INR testing. INR values were reported by patients and recorded. Demographic and clinical data was extracted from the electronic medical record, target INR was set by the treating provider, and TTR was calculated as a surrogate for safe, effective warfarin management. Results: Nine patients (n=9) with APS were identified for this analysis, mean age 16.7 years (range 12-19 years). Demographic and laboratory findings are summarized in Table 1. Most patients had secondary APS due to systemic lupus erythematous (SLE) 78% (n=7) and 22% (n=2) had other primary diagnoses. APS antibody status included single positive in 67% (n=6), double positive in 22% (n=2), and triple positive in 11% (n=1). More specifically, APS criteria were met by persistently elevated LA in 78% (n=7), aCL IgM in 22% (n=2) with overall mean aCL IgM of 34.4 MPL^ (range 9.9-127.9), B2GPI IgG in 11% (n=1) with overall mean B2GPI IgG SGU* of 13.1 (range 0.9-63.3), and B2GPI IgM in 22% (n=2) with overall B2GPI IgM mean of 32.5 SGU (range 3.3-190.9). At time of presentation 67% (n=6) of patients had DVT, 44% (n=4) had PE, 11% (n=1) had arterial TE, and 22% (n=2) presented with DVT & PE. Mean TTR for all patients was 56%. TTR for single positive APS was 66%, double positive APS 39%, and triple positive APS 33%. TTR for secondary APS (SLE) and non-SLE diagnoses was 53% and 68% respectively. Mean dose changes were 11 (range 0-48) with one single positive LA patient requiring 48 dose changes, and two patients with single positive LA not requiring any dose changes. Two patients (22%) developed recurrent clot. One triple positive APS patient developed two DVTs and one non-SLE patient developed recurrent arterial TE. Three patients (33%) had minor bleeding events including mild epistaxis and hematemesis not requiring intervention. One patient (11%) had a major bleeding event, hemoperitoneum from pseudoaneurysm extravasation, while resuming warfarin during post-operative period, and required takeback surgery with sub-therapeutic INR 1.5 at the time of event. Conclusion: The mean TTR for pediatric patients with APS is similar to what is reported in other populations despite the challenge of managing warfarin in this group where the INR may be affected by primary disease modifying medications or disease flares. The risk of recurrent TE remains high in APS patients. Home INR monitors are a safe and effective strategy in managing warfarin anticoagulation in APS patients, reducing time and laboratory monitoring burden for frequent dose changes, which ultimately improves quality of life.Optimizing TTR is important to decrease risk of recurrent TE or bleeding in these high risk APS patients.

Oxidative Stress as a Regulatory Checkpoint in the Production of Antiphospholipid Autoantibodies: The Protective Role of NRF2 Pathway.

Oxidative stress is a well-known hallmark of Antiphospholipid Antibody Syndrome (APS), a systemic autoimmune disease characterized by arterial and venous thrombosis and/or pregnancy morbidity. Oxidative stress may affect various signaling pathways and biological processes, promoting dysfunctional immune responses and inflammation, inducing apoptosis, deregulating autophagy and impairing mitochondrial function. The chronic oxidative stress and the dysregulation of the immune system leads to the loss of tolerance, which drives autoantibody production and inflammation with the development of endothelial dysfunction. In particular, anti-phospholipid antibodies (aPL), which target phospholipids and/or phospholipid binding proteins, mainly β-glycoprotein I (β-GPI), play a functional role in the cell signal transduction pathway(s), thus contributing to oxidative stress and thrombotic events. An oxidation-antioxidant imbalance may be detected in the blood of patients with APS as a reflection of disease progression. This review focuses on functional evidence highlighting the role of oxidative stress in the initiation and progression of APS. The protective role of food supplements and Nuclear Factor Erythroid 2-Related Factor 2 (NRF2) activators in APS patients will be summarized to point out the potential of these therapeutic approaches to reduce APS-related clinical complications.

Profile and clinical relevance of non-criteria antiphospholipid antibodies in patients diagnosed with or highly suspected of APS.

This study investigates the positivity and relevance of non-criteria aPLs with clinical phenotypes in patients highly suspected of or diagnosed with APS. Outpatient cases were included from a prospectively maintained database, and patients were grouped into APS (n = 168), seronegative APS (SNAPS, n = 9), those meeting the diagnostic criteria for clinical events without laboratory results (only-event, n = 15), those that had aPL positivity without clinical manifestations (asymptomatic APA, n = 39), and healthy controls (n = 88). Criteria aPL results and APS-related clinical features were extracted. Sixteen non-criteria aPLs were tested and analysed. LA, aCL and anti-β2 glycoprotein-I were positive in 84.5%, 61.3% and 74.4% of APS patients, and 61.5%, 59.0% and 74.4% of asymptomatic APA patients, respectively. In patients negative for criteria serological tests, 23 out of 24 were positive for at least one non-criteria aPL. Triple-positive patients also had significantly higher tests of some aPLs in comparison with other groups. Stroke was associated with anti-phosphatidyl-inositol (aPI) IgG and anti-phosphatidyl-glycerol (aPG) IgG. Late embryonic loss correlated with aPI IgM, and premature birth/eclampsia was associated with aPI IgG and aPG IgG. There were also positive associations between heart valve lesions and anti-phosphatidylserine-prothrombin (aPS/PT) IgM, APS nephropathy and anti-phosphatidyl-choline IgG or aPS/PT IgG, and livedo reticularis and anti-phosphatidyl-ethanolamine IgM. The prevalence of non-criteria aPLs differed from diagnostic biomarkers in patients diagnosed with or suspected of APS. Detection of aPLs provided additive value in the evaluation of APS-related clinical manifestations.

Prevalence and diagnostic value of non-criteria antiphospholipid antibodies for antiphospholipid syndrome in Chinese patients.

The presence of antiphospholipid antibodies (aPLs) plays a pivotal role in the pathogenesis of antiphospholipid antibody syndrome (APS). This study aimed to examine the diagnostic value of a set of non-criteria aPLs and their relevance with APS-related criteria and extra-criteria manifestations. From a prospectively constructed database, consecutive APS patients consisting of 114 primary APS (PAPS group), 54 with APS secondary to SLE (SAPS group), 9 seronegative APS (SNAPS), as well as 209 patients with systemic lupus erythematosus (SLE) and 88 healthy controls were included in this study. Levels of criteria aPLs, baseline information, and APS-related criteria and extra-criteria features were extracted from the database. Serum levels of non-criteria aPLs including aPC IgG/IgM, aPI IgG/IgM, aPE IgG/IgM/IgA, aPG IgG/IgM/IgA, anti-phosphatidic acid (aPA) IgG/IgM, aSM IgG/IgM, and aPS/PT IgG/IgM were analyzed with AESKULISA® ELISA Test Kits. The addition of aPC IgG/M, aPI IgG/M, aPE IgG/M/A, aSM IgG/M, and aPA IgG/M to aCL or aβ2GPI IgG/M could significantly increase diagnostic sensitivity and accuracy. A significant difference between PAPS or SAPS and HC was presented in all non-criteria aPLs except for aSM IgM and aPG IgA. Eight out of nine SNAPS patients were positive for at least 1 aPL. Pregnancy morbidity was associated with aSM IgM (r = 0.22) and aSM IgG (r = 0.15). Pre-eclampsia or premature birth was associated with aSM IgG (r = 0.16), aPI IgG (r = 0.22), aPC IgG (r = 0.16), and aPG IgG (r = 0.18). Stroke was associated with aPI IgG (r = 0.2). The clinical association was also observed in DVT with aPS/PT IgG (r = 0.17). Valve lesion was positively associated with aSM IgM (Fisher test p = 0.039), APS nephropathy was associated with aPC IgG (OR 3.797), and livedo reticularis was associated with aPE IgM (OR 15.391). Additional detection of non-criteria aPLs including aPC IgG/M, aPE IgG/M/A, aPI IgG/M, aSM IgG/M, and aPA IgG/M could assist in APS diagnosis. The positivity of certain aPLs was statistically associated with both criteria and extra-criteria APS clinical manifestations.

Antiphospholipid Antibody Testing for Anti-cardiolipin and Anti-β2 Glycoprotein I Antibodies Using Chemiluminescence-Based Panels.

Antiphospholipid (antibody) syndrome (APS) is a prothrombotic condition with increased risk for thrombosis and pregnancy-related morbidity. In addition to clinical criteria related to these risks, APS is characterized by the persistent presence of antiphospholipid antibodies (aPL), as detected in the laboratory using a potentially wide variety of assays. The three APS criteria-related assays are lupus anticoagulant (LA), as detected using clot-based assays, and the solid-phase assays of anti-cardiolipin antibodies (aCL) and anti-β2 glycoprotein I antibodies (aβ2GPI), with immunoglobulin subclasses of IgG and/or IgM. These tests may also be used for the diagnosis of systemic lupus erythematosus (SLE). In particular, APS diagnosis/exclusion remains challenging for clinicians and laboratories because of the heterogeneity of clinical presentations in those being evaluated and the technical application and variety of the associated tests used in laboratories. Although LA testing is affected by a wide variety of anticoagulants, which are often given to APS patients to prevent any associated clinical morbidity, detection of solid-phase aPL is not influenced by these anticoagulants, and this thus represents a potential advantage to their application. On the other hand, various technical issues challenge accurate laboratory detection or exclusion of aPL. This report describes protocols for the assessment of solid-phase aPL, specifically aCL and aβ2GPI of IgG and IgM class by means of a chemiluminescence-based assay panel. These protocols reflect tests able to be performed on the AcuStar instrument (Werfen/Instrumentation Laboratory). Certain regional approvals may also allow this testing to be performed on a BIO-FLASH instrument (Werfen/Instrumentation Laboratory).

Comparison of Point-of-Care PT-INR by Hand-Held Device with Conventional PT-INR Testing in Anti-phospholipid Antibody Syndrome Patients on Oral Anticoagulation.

Evidence on agreement of point-of-care (POC) INR testing with laboratory testing in APS patients on oral anticoagulation (OAC), is scarce. This study assessed agreement of paired PT INR testing by a POC device vs. conventional platform-based laboratory test, in APS patients on OAC using a pre-determined definition of agreement. Simultaneous paired PT INR estimation in 92 APS patients was carried out, during October 2020-September 2021. POC INR was performed on capillary blood (pin prick) using the qLabs® PT-INR hand-held device, while laboratory INR estimation was performed using citrated blood (venepuncture) on STA-R Max Analyzer® using STA-NeoPTimal thromboplastin reagent®. Concordance was defined no greater than ± 30% (as per international standards ISO 17593:2007 guidelines) for each paired INR estimation. Agreement between the two was defined as ≥ 90% of paired INR measurements being concordant. 211 paired estimations were performed, within which 190 (90%) were concordant. Good correlation was seen between the 2 methods of INR estimation on Bland Altman plot analysis with an Intra-class correlation coefficient (95% CI) of 0.91(0.882, 0.932). Lab INR range > 4 (P = 0.001) was a significant predictor of higher variability between both methods of INR estimation. Lupus anti-coagulant, other anti-phospholipid antibodies (APL) or triple APL positivity did not result in any statistically significant variation in paired measurements. This study demonstrated good correlation between POC INR measurement and Lab INR estimation and agreement was ascertained between the 2 methods in APS patients on OAC.

Use of Direct Oral Anticoagulants in Patients With Antiphospholipid Syndrome: A Systematic Review and Comparison of the International Guidelines.

Antiphospholipid antibody syndrome (APS) requires long-term anticoagulation to prevent recurrent thrombosis. Direct oral anticoagulants (DOACs) have been increasingly used in APS patients, but contradictory guidelines recommendations on their use do exist. We performed a systematic review of literature including studies investigating the role of DOACs in APS patients. At this aim, PubMed and Cochrane databases were searched according to PRISMA guidelines. We identified 14 studies which investigated the use of DOACs in patients with APS, of which 3 randomized clinical trials (RCTs), 1 post-hoc analysis of 3 RCTs, 7 case series and 3 cohort studies (2 prospective and 1 retrospective). Among DOACs, rivaroxaban was the most used (n = 531), followed by dabigatran (n = 90) and apixaban (n = 46). Regarding guidelines indications, the 2019 European Society of Cardiology (ESC) and American Society of Hematology (ASH) guidelines recommend against the use of DOACs in all APS patients. The European League Against Rheumatism (EULAR), British Society for Haematology (BSH), and International Society on Thrombosis and Haemostasis (ISTH) guidance provided more detailed indications stating that warfarin should be the first-choice treatment but DOACs may be considered in patients (1) already on a stable anticoagulation with a DOAC, (2) with low-quality anticoagulation by warfarin, (3) unwilling/unable to undergo INR monitoring, (4) with contraindications or serious adverse events under warfarin. Patients with arterial APS or triple positivity should be treated with warfarin while venous APS with single or double positivity may be candidate to DOACs, but high-quality studies are needed.

Nanoparticle-Directed Targeting of Clustered PSGL-1 Mitigates Neutrophil-Derived Thrombosis in Antiphospholipid Antibody Syndrome

Multiorgan thromboses and subsequent organ failure are among the more devastating consequences of antiphospholipid antibody syndrome (APS). APS poses a relatively unique risk to patients by virtue of its propensity to cause thrombi of both the arterial and venous vascular systems. While recent studies have explored mechanisms of thrombosis in singular vascular beds, there remains a dearth of targetable effectors of arteriovenous thrombosis in APS. Here, we examine the potential of neutrophils as key players of both arterial and venous thrombosis in APS. From this and previous studies, we have also identified a critical transcriptional regulator in neutrophils whose loss mimics arterial and venous thrombosis susceptibility seen in APS. This factor, Krüppel-like factor 2 (KLF2), is down regulated in APS patients as well as in cells treated with antiphospholipid antibody (APLA) ex vivo. Loss of KLF2 in neutrophils contributes to classic neutrophil activation phenotypes including NETosis, increased tissue factor release, and heightened chemotaxis; remarkably, blocking each of these functions greatly abrogates the thrombotic phenotype. Utilizing the myeloid KLF2 knockout (K2KO) system as a model for aberrant neutrophil activation seen in APS, we have identified clustering of P-selectin glycoprotein ligand 1 (PSGL-1) secondary to actin rearrangement to be operative in neutrophil-mediated thrombosis in arterial and venous systems. While neutralizing antibodies against PSGL-1 have been explored as therapeutic options in APS, there remains a challenge in establishing local specificity to activated immune cells in order to increase efficacy. To circumvent this, we have designed a nanoparticle (NP) based approach that utilizes NPs decorated with anti-PSGL-1 immunoglobulins to better target clustered PSGL-1 on activated neutrophils. PSGL-1 NPs are more effective at inhibiting neutrophil rolling and adhesion in in vitro assays while, incubating activated neutrophils in PSGL-1 NPs prior to infusion attenuates their ability to contribute to both arterial and venous thrombosis. Further, injection of PSGL-1 NPs directly into K2KO mice reduces their extensive thrombotic phenotype. Importantly, this effect occurs at a substantially lower dose of PSGL-1 NPs than that which would be needed of PSGL-1 antibody alone. Finally, PSGL-1 NPs greatly reduce thrombotic burden in mice injected with APLA, diminishing clotting in both arteries and veins. Together, this work identifies key molecular and cellular players in APLA-induced arteriovenous thrombosis. Furthermore, it provides early pre-clinical evidence at specifically targeting clustered PSGL-1 on neutrophils as a viable option in combatting thrombosis in this particularly vulnerable patient population. Disclosures No relevant conflicts of interest to declare.

Mean Platelet Volume as A Marker of Thrombosis Event in Antiphospholipid Syndrome Patients

Antiphospholipid antibody syndrome (APS) is a systemic autoimmune disease associated with venous and/or arterial thrombosis with the presence and persistence of antiphospholipid antibodies (aPL). One of the currently discussed markers related to a high risk of thromboembolism is increased Mean Platelet Volume (MPV). This study aimed to know whether an association exists between MPV and thrombosis event in APS patients. We systematically searched and reviewed studies from MEDLINE, Science Direct and the Cochrane Controlled Trials registry (CENTRAL) from October until November 2018. We use appraisal tools from Critical Appraisal Skills Programme (CASP-UK) for cohort studies. We found two relevant studies to be included in our review.In total, 389 patients consisting 92 APS patient and 297 APS-negative and healthy controls were included. In two studies, the mean of MPV in APS group with thrombosis ranged from 7.85 to 9.22 fl. MPV in APS group with thrombosis was higher than in the APS group without thrombosis and in healthy controls. The platelet size, measured as MPV, reflects platelet reactivity, including aggregation, glycoprotein IIb-IIIa expression and production of more thrombogenic factors. In summary, MPV has a positive correlation with thrombosis event in APS patient. MPV may also be a potential clinical predictor for recurrence of thrombosis in APS patient. We urge that more future prospective studies with larger sample size to be done in order to validate this potential marker.Keywords : Mean platelet volume, thrombosis, antiphospholipid syndrome

Safety and effectiveness of transjugular renal biopsy for systemic lupus erythematosus and antiphospholipid antibody syndrome patients taking antithrombotics.

Renal biopsy is the cornerstone of systemic lupus erythematosus (SLE) nephritis and antiphospholipid syndrome (APS) nephropathy management. However, transcutaneous renal biopsy (TCRB) is hampered by the antithrombotic treatment frequently prescribed for those diseases. Transjugular renal biopsy (TJRB) offers an attractive alternative for patients at increased risk of bleeding. The primary objective of the study was to describe the safety profile and diagnostic performance of TJRB in SLE and APS patients. All SLE and/or APS patients who underwent a renal biopsy in our department (between January 2004 and October 2016) were retrospectively reviewed. Major complications were death, haemostasis nephrectomy, renal artery embolization, red blood cell transfusion, sepsis and vascular thrombosis; macroscopic haematuria, symptomatic perirenal/retroperitoneal bleeding and renal arteriovenous fistula without artery embolization were considered as minor complications. Two hundred and fifty-six TJRBs-119 without antithrombotics (untreated), 69 under aspirin and 68 on anticoagulants and 54 TCRBs without antithrombotics-were analysed. Their major and minor complication rates, respectively, did not differ significantly for the four groups: 0 and 8% for untreated TJRBs, 1 and 6% for aspirin-treated, 6 and 10% for anticoagulant-treated and 2 and 2% for TCRBs. The number of glomeruli sampled and the biopsy contribution to establishing a histological diagnosis was similar for the four groups. TJRBs obtained from SLE and APS patients taking antithrombotics had diagnostic yields and safety profiles similar to those of untreated TCRBs. Thus, TJRB should be considered for SLE and APS patients at risk of bleeding.

DIFFUSE ALVEOLAR HEMORRHAGE IN PATIENTS WITH PRIMARY VS SECONDARY ANTIPHOSPHOLIPID ANTIBODY SYNDROME

SESSION TITLE: Diffuse Lung Disease SESSION TYPE: Original Investigation Posters PRESENTED ON: 10/10/2018 01:00 pm - 02:00 pm PURPOSE: We sought to determine the differences in clinical presentation, management and outcomes of diffuse alveolar hemorrhage in patients with primary and secondary antiphospholipid antibody syndrome (APS) METHODS: We conducted a retrospective chart review of 31 patients with diffuse alveolar hemorrhage (DAH) concurrent with primary and secondary antiphospholipid syndrome from January 1997 to January 2018. The diagnosis of DAH was achieved by i) bronchoalveolar lavage(BAL) revealing grossly hemorrhagic fluid from multiple lobes or increasingly hemorrhagic fluid return on BAL ii) >20% hemosiderin macrophages in BAL iii) DAH confirmed on surgical lung biopsy or autopsy. We reviewed their clinical presentations, laboratory, radiographic, bronchoscopic and pathologic findings and their clinical course. RESULTS: The baseline characteristics were as follows: median age 55 (range 25-88) years; predominantly male (58%); 19.3% smokers. Patients with primary APS (n = 19) and secondary APS (n =12) had similar demographic and laboratory profiles, with the exceptions of 95% of the patients with primary APS had anticardiolipin antibody (n=18) and 63% of them had one of the subtypes of beta-2 glycoprotein antibody (n=12) whilst 75% of the secondary APS patients had a positive anticardiolipin antibody positive(n=9) and 50% of those with a positive beta-2 glycoprotein antibody(n=6). Amongst those who underwent lung biopsies (n=9), 7 patients with primary APS had capillaritis versus only one of the secondary APS patients had capillaritis.DAH was first presentation in 21% (n=4) in primary APS but only in one case (8%) in secondary APS. The management of initial episode of DAH in secondary APS included: 67% required non-invasive ventilation (n=8) and 67% mechanical ventilation (n=8); 41% plasmapheresis (n=5) and 17 % ECMO (n=2). Only 15% of primary APS patients required non-invasive ventilation (n=3), 31% mechanical ventilation(n=6); 21% needed multiple plasmapheresis (n=4) and no patient required ECMO. Despite aggressive management, similar percentage of patients had recurrence of DAH in both subsets with 68% in primary (n=13) and 67% in secondary (n=8) APS. DAH (n=2) and unevaluated sudden onset of respiratory failure (n=1) was the cause of death in primary APS whereas no patients died of DAH or respiratory failure in secondary APS at our institution. CONCLUSIONS: Anticardiolipin antibody is the most common antibody present in primary APS patients. Capillaritis is seen more commonly in primary APS as compared to secondary APS. More aggressive respiratory support was needed in DAH cases in the setting of secondary APS. CLINICAL IMPLICATIONS: DAH in the setting of APS, especially secondary APS can be severe. Prompt recognition and early aggressive treatment are needed. DISCLOSURES: No relevant relationships by Misbah Baqir, source=Web Response No relevant relationships by Jay Ryu, source=Web Response No relevant relationships by Swathi Sangli, source=Web Response No relevant relationships by Ting Yang, source=Web Response

Aspirin or heparin or both in the treatment of recurrent spontaneous abortion in women with antiphospholipid antibody syndrome: a meta-analysis of randomized controlled trials

Objective: This study was designed to evaluate the efficacy of aspirin or heparin or both in the treatment for recurrent spontaneous abortion (RSA) in women with antiphospholipid antibody syndrome (APS).Methods: Systematic searches for randomized clinical trials (RCTs) evaluating on live birth and preterm delivery, preeclampsia, intrauterine growth restriction, gestational diabetes, bleeding of RSA with APS patients receiving aspirin, and heparin therapy were carried out, from PubMed, EMBASE, ScienceDirect, and CNKI. Related data were extracted from eligible studies and then subjected to Reviewer Manage 5.3 for analysis. Relative risk (RR) and its 95% confidence interval were calculated.Results: Nineteen publications with randomized controlled trials were selected for this study, which included a total of 1251 pregnant patients with diagnosis of RSA with APS. With respect to live birth, it was remarkably improved in aspirin plus heparin or heparin alone group [RR =1.23, 95% CI (1.12–1.36), p < .0001; RR = 1.18, 95% CI (1.03–1.35), p = .02]; aspirin alone group, however, there was no statistically significant difference compare to placebo [RR = 0.97, 95% CI (0.80–1.16), p = .71]. Meanwhile, aspirin plus heparin therapy did not significantly reduce the risk of recurrent placenta-mediated pregnancy complications including preterm birth, intrauterine growth retardation (IUGR), gestational diabetes, and minor bleeding. A beneficial therapeutic effect of heparin alone therapy was found on preventing preterm birth and low-dose aspirin plus heparin therapy was significant reduce the risk of preeclampsia.Conclusion: An improvement of pregnancy outcomes in women with RSA and APS can be achieved by treatment strategies combining low-dose aspirin plus heparin or heparin alone. Aspirin alone, by contrast, seemed inferior to other treatments in achieving more live birth.

Plasma levels of high-mobility group box 1 and soluble receptor for advanced glycation end products in primary antiphospholipid antibody syndrome patients.

IntroductionMany studies have demonstrated elevated circulating levels of high-mobility group box 1 (HMGB1) and decreased circulating levels of soluble receptor for advanced glycation end products (sRAGE) in patients with autoimmune diseases. In the present study, we investigated plasma levels of both HMGB1 and sRAGE in primary antiphospholipid syndrome (pAPS) patients.MethodsWe prospectively recruited 11 pAPS patients, 17 antiphospholipid antibody (APA)-positive SLE patients without APS manifestations (APA+SLE) and 12 SLE patients with secondary APS (APS+SLE). We also recruited 10 healthy controls (HCs). Plasma levels of HMGB1 and sRAGE were determined using sandwich ELISA kits. In addition, plasma levels of HMGB1 were also determined using Western blot in 6 pAPS patients and 6 HCs.ResultsThere was no significant difference in plasma levels of HMGB1 measured by ELISA among subgroups of the enrolled subjects. In addition, there was no significant difference in plasma levels of HMGB1 measured by Western blot between pAPS patients and HCs. On the other hand, we observed a trend toward lower plasma levels of sRAGE in APA+SLE or APS+SLE patients when compared with HCs. However, there was no significant difference in plasma levels of sRAGE between pAPS patients and HCs, or between APA+SLE patients and APS+SLE patients.ConclusionThere was no significant difference in plasma levels of sRAGE or HMGB1 between pAPS patients and HCs. Plasma levels of sRAGE/HMGB1 could not be utilized to differentiate between APA+SLE and APS+SLE patients.

Patient-derived anti-β2GP1 antibodies recognize a peptide motif pattern and not a specific sequence of residues.

Antiphospholipid antibody syndrome is an autoimmune disease characterized by the presence of so-called antiphospholipid antibodies and clinical manifestations such as recurrent thromboembolic or pregnancy complications. Although the main antigenic determinant for antiphospholipid antibodies has been identified as the β-2-glycoprotein 1 (β2GP1), the precise epitope recognized by antiphospholipid antibodies still remains largely unknown. In the study herein, we wanted to identify a sequence in domain I of β2GP1 able to induce the proliferation of CD4+ T cells isolated from antiphospholipid antibody syndrome patients, but not from healthy donors, and to interact with antiphospholipid antibodies. We have characterized a sequence in domain I of β2GP1 that triggers CD4+ T-cell proliferation. A comparison of this sequence with the previously reported binding of antiphospholipid antibodies to discontinuous epitope R39-R43 reveals the presence of an indeterminate motif in β2GP1, in which the polarity determines the characteristics and specificity of antiphospholipid antibodies-interacting motifs. Using point mutations, we characterized the main antiphospholipid antibodies-interacting motif as ϕϕϕζζFxC, but also established ϕϕϕζζFxϕ-related motifs as potential antiphospholipid antibodies epitopes, in which ϕ represents nonpolar residues and ζ polar residues, with charges of the residues not being involved. Of specific importance, these different motifs are present at least once in all antiphospholipid antibodies-related receptors described so far. We have further demonstrated, in vitro, that peptides and domains of β2GP1 containing these motifs were able to interact with antiphospholipid antibodies and inhibit their monocyte activating activity. These results established that the antiphospholipid antibodies-interacting motifs are determined by the polarity, but not by the sequence or charge, of amino acids. These data could also contribute to the future development of more sensitive and specific diagnostic tools for antiphospholipid antibody syndrome determination and potential peptide- or β2GP1 domain-based clinical therapies.

Dyslipidemia and its relationship with antiphospholipid antibodies in APS patients in North Kerala.

Antiphospholipid antibody syndrome (APS) is one of the most common acquired thrombophilic disorders resulting in arterial and venous thromboses. APS is a major cause for cerebrovascular accidents or stokes, myocardial infarction, venous thromboembolism and recurrent abortions/pregnancy losses especially in young patients. APS patients have an increased risk of atherosclerotic cardiovascular events. There are only two studies on lipid abnormalities in APS patients. None of them have studied the relationship between individual laboratory tests for APS and lipid profile abnormalities. Here we describe the significance of the relationship between various APS tests and lipid profile abnormalities in a subset of APS patients who presented with arterial thrombosis in a tertiary care hospital. The study was conducted at Government Medical College, which is a tertiary care referral hospital. All patients who presented to the medicine department with APS during a two-year period were studied. A patient was considered to be positive for anticardiolipin (aCL) antibody or anti-β2 glycoprotein (anti-β2G) if the titer was more than 15 IU/mL, and a high titer was considered to be more than 40 IU/mL for Immunoglobulin (lg) IgG and IgM isotypes. The fasting lipid profile was measured in all patients, and lipid profile abnormalities were defined with cutoffs of low-density lipoprotein (LDL) levels of >150 mg/dL, triglyceride (TG) levels of >150 mg/dL, and high-density lipoprotein (HDL) levels of <40 mg/dL. The relationship between lipid abnormalities and individual tests for APS, aCL IgG and IgM and anti-β2G IgG and IgM, were determined by statistical analysis. The study population included 77 APS patients, with 53% of patients between 20 and 40 years. The commonest abnormality in the lipid profile test was elevated TG levels of >150 mg/dL in 51.9% of the patients, followed by low HDL levels (<40 mg/dL) in 38.9% of the patients and high LDL levels (>150 mg/dL) in 40.2% of the patients. There was a statistically significant relationship between anti-β2G IgG levels and HDL and LDL levels, but not TG levels. Only LDL levels had a statistically significant relationship with aCL IgM levels. None of the lipid abnormalities had any statistically significant relationship with aCL IgG levels. This study highlights the importance of testing lipid profile abnormalities in APS patients and the existence of a statistically significant relationship between antiphospholipid antibody tests and lipid profile abnormalities.

Apheresis and intravenous immunoglobulins used in addition to conventional therapy to treat high-risk pregnant antiphospholipid antibody syndrome patients. A prospective study

Pregnant women with triple antibody positive antiphospholipid syndrome (APS) who have had thrombosis or a history of early, severe pregnancy complications are generally considered at high risk of pregnancy loss. The objectives of this study were to investigate the efficacy and safety of a relatively new treatment protocol used in addition to conventional therapy in high-risk pregnant patients affected with primary APS. The study’s two inclusion criteria were: (1) the presence of triple antiphospholipid positivity, (2) previous thrombosis and/or a history of one or more early, severe pregnancy complications.Eighteen pregnancies occurring between 2002 and 2015 in 14 APS patients, (mean age 34.8±3.6 SD) were monitored. All 14 (100%) patients had triple antiphospholipid positivity. In addition, six of them (42.8%) had a history of thrombosis, four (28.6%) had one or more previous early and severe pregnancy complications, and four (30.8%) met both clinical study criteria.The study protocol included weekly plasmapheresis or immunoadsorption and fortnightly 1g/kg intravenous immunoglobulins. Seventeen of the pregnancies (94.4%) produced live neonates, all born between the 26th and 37th weeks of gestation (mean 33.1±3.5 SD). One female (5.5%), born prematurely at 24 weeks, died of sepsis a week after birth. There were two cases (11.1%) of severe pregnancy complications. No treatment side effects were registered. Given the high live birth rate and the safety associated to it, the study protocol described here could be taken into consideration by medical teams treating high-risk APS pregnant patients.

Antibodies to age-β2 glycoprotein I in patients with anti-phospholipid antibody syndrome.

Anti-phospholipid antibody syndrome (APS) is a systemic autoimmune disease characterized clinically by arterial and/or venous thromboses, recurrent abortions or fetal loss and serologically by the presence of 'anti-phospholipid antibodies' (aPL). The main target antigen of the antibodies is β2 glycoprotein I (β2 GPI). Post-translational oxidative modifications of the protein have been widely described. In this study we aimed to analyse sera reactivity to glucose-modified β2 GPI (G-β2 GPI). Sera collected from 43 patients with APS [15 primary APS (PAPS) and 28 APS associated with systemic lupus erythematosus (SLE) (SAPS)], 30 with SLE, 30 with rheumatoid arthritis (RA) and 40 healthy subjects were analysed by an enzyme-linked immunosorbent assay (ELISA) using a G-β2 GPI. Nine of 15 consecutive PAPS out-patients (60%) and 16 of 28 SAPS (57.1%) showed serum antibodies [immunoglobulin (Ig)G class] against G-β2 GPI (anti-G-β2 GPI) by ELISA. The occurrence of anti-G-β2 GPI was significantly higher in APS patients compared to patients suffering from SLE. No RA patients or control healthy subjects resulted positive for anti-G-β2 GPI. Of note, aG-β2 GPI prompted to identify some APS patients (four PAPS and seven SAPS), who were negative in the classical anti-β2 GPI test. Moreover, in APS patients, anti-G-β2 GPI titre was associated significantly with venous thrombosis and seizure in APS patients. This study demonstrates that G-β2 GPI is a target antigen of humoral immune response in patients with APS, suggesting that β2 GPI glycation products may contain additional epitopes for anti-β2 GPI reactivity. Searching for these antibodies may be useful for evaluating the risk of clinical manifestations.

A new cytofluorimetric approach to evaluate the circulating microparticles in subjects with antiphospholipid antibodies

IntroductionGrowing evidence supports the idea that microparticles (MPs) could contribute to the pathogenesis of the thrombotic phenomena associated with antiphospholipid antibody syndrome (APS), inducing a hypercoagulable state. But, to date, different approaches to evaluate circulating MPs and conflicting results have been reported. Materials and methodsWe have characterized the different circulating subpopulations of MPs in APS patients, and in asymptomatic aPL-positive subjects (carriers) by examining the correlation between the amount and phenotype of MPs and the clinical parameters. Forty-eight subjects were enrolled: 16 with primary APS, 16 aPL-positive, but without clinical criteria for APS (carriers), and 16 healthy subjects. The levels of MPs were evaluated using a new cytofluorimetric approach based on BD Horizon Violet Proliferation dye (VPD) 450. Results and conclusionsUsing a new detection cytofluorimetric approach, we demonstrated that the AnnV-negative MPs, underestimated/or excluded in the previous studies, are a large subset of circulating MPs. Also, the levels of MPs in the plasma of aPL positive subjects indicate a state of cellular activation, which is much more pronounced in patients with APS compared to aPL carriers. Moreover, the preliminary data of our pilot study suggest that the evaluation of circulating MPs, in particular PMPs and EMPs, could be used as a surrogate biomarker for platelet and vascular damage monitoring and, if confirmed in a more numerous cohort of patients, it could be used as a prognostic factor to identify aPL positive subjects at higher risk of developing thrombosis.

Thrombophilic state in young patients with acute myocardial infarction.

The prevalence of thrombophilia and dyslipidemia among young survivors of acute coronary syndrome has not been clearly defined. The purpose of the current study was to investigate the prevalence of multiple markers of thrombophilia and dyslipidemia in a cohort of consecutive young survivors of acute coronary syndrome. The study cohort included 156 consecutive young patients (men <45 and women <50 years), admitted to the intensive cardiac care unit with newly diagnosed acute coronary syndrome. Analysis included baseline, clinical and epidemiological characteristics, angiographic coronary anatomy, echocardiographic evaluation, extensive lipid and thrombophilia laboratory profiles, and in-hospital and 1-year clinical outcomes for all patients. Acute myocardial infarction was diagnosed in 142 (92 %) patients, of whom 108 (72 %) had ST-segment elevation. Eighteen (12 %) patients had no traditional risk factors. Low levels of high-density lipoprotein (<40 mg/dL) were found in 101 (65 %) patients, and 49 (34 %) patients had elevated levels of lipoprotein(a) (Lp(a)) (>30 mg/dL). Eighteen (12 %) patients were diagnosed with antiphospholipid antibody syndrome (APS), and 73 (47 %) had at least one laboratory finding consistent with thrombophilia. Patients with APS had significantly higher levels of Lp(a) (46 ± 32 vs. 29 ± 31 mg/dL, p = 0.005). APS is a common prothrombotic state found in young survivors of acute coronary syndrome. Lp(a) levels are elevated among APS patients who present with premature acute coronary syndrome.