The prevalence and incidence of thrombotic primary antiphospholipid syndrome in adults aged 18-49 years: A population-based study in a mountain community in northern Italy.

OBJECTIVE: To estimate prevalence and incidence of thrombotic Primary Antiphospholipid Syndrome (PAPS) in the general population aged 18-49 years. METHODS: The study was carried out in Valtrompia, a valley in northern Italy, in 2011-2015. The identification of PAPS cases leveraged three integrated sources: 1) Rheumatology Unit at the University Hospital; 2) General Practitioners; 3) hospital discharge codes of patients admitted for thrombotic events. RESULTS: Prevalence and incidence were estimated as 22.9 (95% C.I. 11.4-41.0) and 5.0 (2.6-8.7) cases per 100,000 individuals, respectively. The estimates were 28.3 and 4.8, and 17.2 and 5.1 in males and females, respectively. The type of disease onset was mainly of arterial type in men and venous in women. CONCLUSIONS: Thrombotic PAPS was found to be a rare disease in this population-based study. Prevalence and incidence were not significantly different between males and females aged 18-49 years, but a different type of onset was observed.

Pregnancy in antiphospholipid syndrome: what should a rheumatologist know?

This review focuses on the management of reproductive issues in women who have antiphospholipid syndrome (APS) or are carriers of antiphospholipid antibodies (aPL). The importance of aPL detection during preconception counselling relies on their pathogenic potential for placental insufficiency and related obstetric complications. The risk of adverse pregnancy outcomes can be minimized by individualized risk stratification and tailored treatment aimed at preventing placental insufficiency. Combination therapy of low-dose acetylsalicylic acid and heparin is the mainstay of prophylaxis during pregnancy; immunomodulation, especially with hydroxychloroquine, should be considered in refractory cases. Supplementary ultrasound surveillance is useful to detect fetal growth restriction and correctly tailor the time of delivery. The individual aPL profile must be considered in the stratification of thrombotic risk, such as during assisted reproduction techniques requiring hormonal ovarian stimulation or during the follow-up after pregnancy in order to prevent the first vascular event.

Damage measured by Damage Index for Antiphospholipid Syndrome (DIAPS) in antiphospholipid antibody-positive patients included in the APS ACTION registry.

OBJECTIVES: Our primary objective was to quantify damage burden measured by Damage Index for Antiphospholipid Syndrome (DIAPS) in aPL-positive patients with or without a history of thrombosis in an international cohort (the APS ACTION cohort). Secondly, we aimed to identify clinical and laboratory characteristics associated with damage in aPL-positive patients. METHODS: In this cross-sectional study, we analysed the baseline damage in aPL-positive patients with or without APS classification. We excluded patients with other autoimmune diseases. We analysed the demographic, clinical and laboratory characteristics based on two subgroups: (i) thrombotic APS patients with high vs low damage; and (ii) non-thrombotic aPL-positive patients with vs without damage. RESULTS: Of the 826 aPL-positive patients included in the registry as of April 2020, 586 with no other systemic autoimmune diseases were included in the analysis (412 thrombotic and 174 non-thrombotic). In the thrombotic group, hyperlipidaemia (odds ratio [OR] 1.82; 95% CI 1.05, 3.15; adjusted P = 0.032), obesity (OR 2.14; 95% CI 1.23, 3.71; adjusted P = 0.007), aß2GPI high titres (OR 2.33; 95% CI 1.36, 4.02; adjusted P = 0.002) and corticosteroid use (ever) (OR 3.73; 95% CI 1.80, 7.75; adjusted P < 0.001) were independently associated with high damage at baseline. In the non-thrombotic group, hypertension (OR 4.55; 95% CI 1.82, 11.35; adjusted P = 0.001) and hyperlipidaemia (OR 4.32; 95% CI 1.37, 13.65; adjusted P = 0.013) were independent predictors of damage at baseline; conversely, single aPL positivity was inversely correlated with damage (OR 0.24; 95% CI 0.075, 0.77; adjusted P = 0.016). CONCLUSIONS: DIAPS indicates substantial damage in aPL-positive patients in the APS ACTION cohort. Selected traditional cardiovascular risk factors, steroids use and specific aPL profiles may help to identify patients more prone to present with a higher damage burden.

Associations Among Antiphospholipid Antibody Types, Isotypes, and Titers: An AntiPhospholipid Syndrome Alliance for Clinical Trials and InternatiOnal Networking (APS ACTION) Study.

Several antiphospholipid antibody (aPL) profiles ("triple" and lupus anticoagulant [LA] positivity) are associated with a higher risk for clinical manifestations of antiphospholipid syndrome (APS). Further risk is correlated with higher levels of anticardiolipin antibody (aCL) and anti-ß2 glycoprotein-I antibody (aß2GPI), and with aPL persistence. Given that the 3 aPL tests detect partially overlapping sets of antibodies, the primary goal of this study was to characterize the associations among aPL tests using AntiPhospholipid Syndrome Alliance for Clinical Trials and InternatiOnal Networking (APS ACTION) core laboratory data. The APS ACTION Registry includes annually followed adult patients with positive aPL based on the Revised Sapporo Classification Criteria. We analyzed baseline and prospective core laboratory data of the registry for associations among aPL tests using the Spearman rank correlation with Bonferroni-adjusted significance level for multiple comparisons. An aPL Load was calculated based on 6 tests (aCL IgG/IgM/IgA and aß2GPI IgG/IgM/IgA); a receiver operating characteristic curve was used to evaluate the diagnostic performance of the aPL Load in predicting LA positivity. In 351 patients simultaneously tested for LA, aCL, and aß2GPI, the frequency of moderate-to-high (≥40 U) titers of aCL and aß2GPI IgG/IgM/IgA was higher in patients who were positive for LA vs those who were negative. An aPL Load was calculated for each patient to assess the overall aPL burden. For every 1-point increase in the aPL Load, the possibility of a positive LA test increased by 32% (odds ratio, 1.32; 95% CI, 1.2-1.5; P < .001). Based on core laboratory data from a large international registry, most aPL enzyme-linked immunosorbent assay ≥40 U and a high calculated aPL Load combining 6 aPL enzyme-linked immunosorbent assays were predictive of a positive LA. These data suggest that the combined quantitative burden of aPL may provide a mechanistic explanation of a positive LA.

CXCL-13 serum levels in patients with rheumatoid arthritis treated with abatacept.

OBJECTIVES: C-X-C motif chemokine 13 (CXCL-13), which is expressed by synovial follicular dendritic cells and activated mature antigen-experienced T-helper cells, has been described as a surrogate marker of lymphoid phenotype of synovitis in rheumatoid arthritis (RA). A preferential response to anti-interleukin-6 receptor (IL-6R) as compared to anti-tumour necrosis factor alpha (TNFα) monotherapy has been described in patients with increased levels of CXCL-13. We hypothesised that serum levels of CXCL-13 could be used as a biomarker of response to treatment with abatacept (ABA), a T-cell co-stimulation blocker. METHODS: Serum levels of CXCL-13 and of soluble intracellular adhesion molecule 1 (sICAM-1) (a putative marker of the myeloid subtype of synovitis) were measured by indirect solid-phase enzyme immunoassays, before (T0) and after 6 months of therapy with ABA (T6) in 63 patients with RA. Circulating T follicular helper cells and B cell subpopulations were identified by flow-cytometry. RESULTS: At T0, CXCL-13 serum levels were higher in RA patients than in healthy controls (p=0.0001) and correlated with disease activity, while no difference between the two groups was observed as far as sICAM-1 levels. Serum levels of CXCL-13 levels decreased after therapy with ABA both in patients who achieved a clinical response (p<0.01) and in non-responders (p=0.01), whereas sICAM-1 levels did not significantly change. When comparing RA patients who responded to ABA with non-responders no significant difference of baseline serum levels of CXCL-13 was observed. CONCLUSIONS: CXCL-13 serum levels are raised in RA patients and decrease after therapy with ABA. We were not able to demonstrate that serum CXCL-13 levels predict the clinical response to ABA in RA patients.

Gender differences in primary antiphospholipid syndrome with vascular manifestations in 433 patients from four European centres.

OBJECTIVES: Gender can influence incidence and clinical course of autoimmune diseases (ADs). Antiphospholipid syndrome (APS) is a rare AD characterised by thromboses and/or pregnancy morbidities and antiphospholipid antibodies (aPL) positivity. Our aim is to conduct a gender-oriented analysis of primary thrombotic APS (t-APS). METHODS: Consecutive patients diagnosed with primary t-APS, followed from 1967 to 2019 in four European Centres, were enrolled. RESULTS: The cohort included 296 women and 137 men. Median age at onset [31 (24-46) vs. 41 (29-53) years, p<0.001] was lower in females. In women, venous thromboses were more frequent while, among males, arterial events prevailed. During follow-up, 14% of patients suffered at least two relapses and this occurred especially among males (22% vs. 10%, p=0.001). No gender differences were found in the aPL profile (33% single, 24% double and 43% triple aPL positivity). Most patients had concomitant risk factors (RFs) for thrombosis: established cardiovascular RFs were represented especially among men while estrogenic exposure was the main RF in women. CONCLUSIONS: Women presented mostly with venous thromboses at a younger age, while men with arterial events, later in life and suffered more recurrent events. This different frequency of arterial and venous thromboses could be attributed mainly to the presence of additional RFs rather than to biological gender-specific issues. However, some RFs are exclusive or more represented in one gender rather than the other, so assessing the link of causality between gender and manifestations of t-APS remains difficult.

Blood biomarkers recommended for diagnosing and monitoring IgG4-related disease. Considerations from the ERN ReCONNET and collaborating partners.

Immunoglobulin G4 (IgG4)-related disease (IgG4-RD) is a chronic, clinically heterogenous fibroinflammatory condition, characterised by an accumulation of IgG4 secreting plasma cells in affected tissues and associated with increased serum IgG4 concentrations. Despite a growing recognition of the disease among clinicians from different specialties worldwide, its indolent nature, lack of a single diagnostic test and ability to mimic other malignant, infective and inflammatory conditions, makes the diagnosis challenging. As treatment options evolve, biomarkers correlating with disease activity, predicting prognosis and response to treatment are deemed required. A multidisciplinary panel of experts from the European Reference Network for Rare and Complex Connective tissue diseases (ERN ReCONNET) and affiliated international partners have performed a narrative literature search and reviewed the current evidence of biomarkers in IgG4-RD, including immunoglobulins, cytokines, chemokines and other soluble immune mediators, and cellular components of the immune system. The aim of this paper is to provide useful information for clinicians as to the utility of biomarkers for diagnosing and monitoring IgG4-RD in clinical routine and sets out recommendations for clinical decision making.

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

BACKGROUND: The combination of low-dose aspirin (LDA) and low-molecular-weight heparin (LMWH) until the end of gestation are the currently the accepted standard of care for the treatment of antiphospholipid-related obstetric disorders. In refractory cases, hydroxychloroquine (HCQ) can be added to this standard of care. OBJECTIVE: To evaluate the haemostatic safety of LDA and LMWH (medium to high prophylactic doses) during pregnancy and the puerperium in women with both full-blown obstetric antiphospholipid syndrome (OAPS) (Sydney criteria) and noncriteria - incomplete - OAPS. STUDY DESIGN: Retrospective/prospective multicentre observational study. Obstetric background, laboratory categories, delivery mode, antithrombotic regimens and bleeding complications were compared. SETTING: A total of 30 tertiary European hospitals. PATIENTS: Mainly, Caucasian/Arian pregnant women were included. Other ethnicities were minimally present. Women were controlled throughout pregnancy and puerperium. MAIN OUTCOME MEASURES: The primary end-point was to evaluate the number of major and minor haemorrhagic complications in this cohort of women. Neuraxial anaesthetic bleeding complications were particularly assessed. Secondly, we aimed to compare local/general bleeding events between groups. RESULTS: We studied 1650 women, of whom 1000 fulfilled the Sydney criteria of the OAPS and 650 did not (noncriteria OAPS). Data on antithrombotic-related complications were available in 1075 cases (65.15%). Overall, 53 (4.93%) women had bleeding complications, with 34 being considered minor (3.16%) and 19 major (1.76%). Neither obstetric complications nor laboratory categories were bleeding-related. Assisted vaginal delivery and caesarean section were related to local haemorrhage. Heparin doses and platelet count were not associated with major bleeding. CONCLUSIONS: LDA and medium to high prophylactic LMWH during pregnancy in women with full-blown OAPS/noncriteria OAPS are safe. A slight increase in bleeding risk was noted in instrumental deliveries. No women who underwent spinal or epidural anaesthesia suffered bleeding complications. No haemorrhage was observed in cases where HCQ was added to standard therapy.

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

OBJECTIVES: To compare clinical features, laboratory data and fetal-maternal outcomes between 1000 women with obstetric APS (OAPS) and 640 with aPL-related obstetric complications not fulfilling Sydney criteria (non-criteria OAPS, NC-OAPS). METHODS: This was a retrospective and prospective multicentre study from the European Registry on Obstetric Antiphospholipid Syndrome. RESULTS: A total of 1650 women with 5251 episodes, 3601 of which were historical and 1650 latest episodes, were included. Altogether, 1000 cases (OAPS group) fulfilled the Sydney classification criteria and 650 (NC-OAPS group) did not. Ten NC-OAPS cases were excluded for presenting thrombosis during follow-up. All cases were classified as category I (triple positivity or double positivity for aPL) or category II (simple positivity). Overall, aPL laboratory categories showed significant differences: 29.20% in OAPS vs 17.96% in NC-OAPS (P < 0.0001) for category I, and 70.8% in OAPS vs 82% in NC-OAPS (P < 0.0001) for category II. Significant differences were observed when current obstetric complications were compared (P < 0.001). However, major differences between groups were not observed in treatment rates, livebirths and thrombotic complications. In the NC-OAPS group, 176/640 (27.5%) did not fulfil Sydney clinical criteria (subgroup A), 175/640 (27.34%) had a low titre and/or non-persistent aPL positivity but did meet the clinical criteria (subgroup B) and 289/640 (45.15%) had a high aPL titre but did not fulfil Sydney clinical criteria (subgroup C). CONCLUSION: Significant clinical and laboratory differences were found between groups. Fetal-maternal outcomes were similar in both groups when treated. These results suggest that we could improve our clinical practice with better understanding of NC-OAPS patients.

"APS pregnancy - The offspring".

BACKGROUND: Antiphospholipid antibody syndrome (APS) is an autoimmune disease that affects women in childbearing age. In recent years, great improvements were achieved in the management of pregnancies in these women. Prematurity could be an issue in these pregnancies, mainly due to the direct pathogenic effect of antiphospholipid antibodies (aPL) on the placental surface. Maternal IgG aPL can cross the placenta and theoretically interact with the growing fetus; it could reach the fetal brain because of the incompleteness of the fetal blood-brain barrier: whether this can have an effect on brain development is still debated. Neonatal thrombosis episodes have been described in children positive for aPL, not always associated with maternal antibody positivity, suggesting the hypothesis of a possible aPL de novo synthesis in fetus and neonates. METHODS: A keyword-based literature search was conducted. We also described a case of neonatal catastrophic antiphospholipid syndrome (CAPS). RESULTS: Offspring of patients with APS are generally healthy but the occurrence of neonatal thrombosis or minor neurological disorders were reported. CONCLUSIONS: The limited number of the available data on this sensitive issue supports the need for further studies. Clinical follow-up of children of mothers with APS seems to be important to exclude, in the neonatal period, the occurrence of aPL associated pathological events such as thrombosis, and in the long-term, impairment in learning skills or behavioral problems.

Cluster analysis for the identification of clinical phenotypes among antiphospholipid antibody-positive patients from the APS ACTION Registry.

OBJECTIVE: This study aimed to use cluster analysis (CA) to identify different clinical phenotypes among antiphospholipid antibodies (aPL)-positive patients. METHODS: The Alliance for Clinical Trials and International Networking (APS ACTION) Registry includes persistently positive aPL of any isotype based on the Sydney antiphospholipid syndrome (APS) classification criteria. We performed CA on the baseline characteristics collected retrospectively at the time of the registry entry of the first 500 patients included in the registry. A total of 30 clinical data points were included in the primary CA to cover the broad spectrum of aPL-positive patients. RESULTS: A total of 497 patients from international centres were analysed, resulting in three main exclusive clusters: (a) female patients with no other autoimmune diseases but with venous thromboembolism (VTE) and triple-aPL positivity; (b) female patients with systemic lupus erythematosus, VTE, aPL nephropathy, thrombocytopaenia, haemolytic anaemia and a positive lupus anticoagulant test; and (c) older men with arterial thrombosis, heart valve disease, livedo, skin ulcers, neurological manifestations and cardiovascular disease (CVD) risk factors. CONCLUSIONS: Based on our hierarchical cluster analysis, we identified different clinical phenotypes of aPL-positive patients discriminated by aPL profile, lupus or CVD risk factors. Our results, while supporting the heterogeneity of aPL-positive patients, also provide a foundation to understand disease mechanisms, create new approaches for APS classification and ultimately develop new management approaches.

Beyond thrombosis: Anti-ß2GPI domain 1 antibodies identify late pregnancy morbidity in anti-phospholipid syndrome.

Antibodies against ß2 glycoprotein I (anti-ß2GPI) have been identified as the main pathogenic autoantibody subset in anti-phospholipid syndrome (APS); the most relevant epitope is a cryptic and conformation-dependent structure on ß2GPI domain (D) 1. Anti-ß2GPI domain profiling has been investigated in thrombotic APS, leading to the identification of antibodies targeting D1 as the main subpopulation. In contrast, scarce attention has been paid to obstetric APS, hence this study aimed at characterizing the domain reactivity with regards to pregnancy morbidity (PM). To this end, 135 women with persistently positive, medium/high titre anti-ß2GPI IgG, without any associated systemic autoimmune diseases and at least one previous pregnancy were included: 27 asymptomatic carriers; 53 women with obstetric APS; 20 women with thrombotic APS; and 35 women with both thrombotic and obstetric complications. Anti-D1 and anti-D4/5 antibodies were tested using a chemiluminescent immunoassay and a research ELISA assay, respectively (QUANTA Flash® ß2GPI Domain 1 IgG and QUANTA Lite® ß2GPI D4/5 IgG, Inova Diagnostics). Positivity for anti-D1 antibodies, but not anti-D4/5 antibodies, was differently distributed across the 4 subgroups of patients (p < 0.0001) and significantly correlated with thrombosis (χ2 = 17.28, p < 0.0001) and PM (χ2 = 4.28, p = 0.039). Patients with triple positivity for anti-phospholipid antibodies displayed higher anti-D1 titres and lower anti-D4/5 titres compared to women with one or two positive tests (p < 0.0001 and p = 0.005, respectively). Reactivity against D1 was identified as a predictor for PM (OR 2.4, 95% confidence interval [CI] 1.2-5.0, p = 0.017); in particular, anti-D1 antibodies were predictive of late PM, conveying an odds ratio of 7.3 (95% CI 2.1-25.5, p = 0.022). Positivity for anti-D1 antibodies was not associated with early pregnancy loss. Anti-D4/5 antibodies were not associated with clinical APS manifestations. As a whole, our data suggest that anti-D1 antibodies are significantly associated not only with thrombosis, but also with late PM, while positive anti-D4/5 antibodies are not predictive of thrombosis or PM.

A comprehensive review of the clinical approach to pregnancy and systemic lupus erythematosus.

Nowadays, most of the young women affected by Systemic Lupus Erythematosus (SLE) can carry out one or more pregnancies thanks to the improvement in treatment and the consequent reduction in morbidity and mortality. Pregnancy outcome in these women has also greatly improved in the last decades. A correct timing for pregnancy (tailored on disease activity and established during a preconception counselling), together with a tight monitoring during the three trimesters and the post-partum period (to timely identify and treat possible obstetric complications or maternal disease flares), as well as the concept of multidisciplinary management, are currently milestones of the management of pregnancy in SLE patients. Nevertheless, the increasing knowledge on the compatibility of drugs with pregnancy has allowed a better treatment of these patients, by choosing medications that control maternal disease activity without harming the foetus. However, particular attention and strict monitoring should be dedicated to SLE pregnant women in particular clinical settings: patients with lupus nephritis and patients with aPL positivity or Antiphospholipid syndrome, who are at higher risk for maternal and foetal complications, but also patients with anti-Ro/SSA and/or anti-La/SSB antibodies, because of the risk of neonatal lupus. A discussion on family planning, as well as counselling on contraception, should be part of the everyday-practice for physicians caring for SLE women during their reproductive age. Another issue is the possible reduction of fertility in these women, that can be due to different reasons. Consequently, the request for assisted reproduction techniques has been increasing in the last years, so that rheumatologists and gynaecologists should be prepared to counsel SLE patients also in this particular setting.

Efficacy and safety of off-label use of rituximab in refractory lupus: data from the Italian Multicentre Registry.

OBJECTIVES: To evaluate the efficacy and safety of rituximab (RTX) in patients with systemic lupus erythematosus (SLE) refractory to standard therapy in the clinical practice setting. METHODS: 145 SLE patients (ACR criteria) were treated with RTX in 11 Italian Centres: 118 with two infusions (1 g), two weeks apart; 27 with 4 infusions (375 mg/m2), one week apart, followed in 10 cases by two further doses, after 1 and 2 months. Systemic complete response (CR) was defined as European Consensus Lupus Activity Measurement (ECLAM) score ≤1 and partial response (PR) as 1< ECLAM ≤3. Renal CR (RCR) and renal PR (RPR) were defined according to EULAR recommendations for management of lupus nephritis. RESULTS: Data from 134 (92.4%) patients were available. The mean±SD follow-up was 27.3±18.5 months. After the first course of RTX, CR or PR were observed in 85.8% and CR in 45.5% of cases; RCR or RPR in 94.1% and RCR in 30.9% of patients after 12-month follow-up. Disease flares occurred in 35.1% and renal flares in 31.2% of patients during observational period. Among patients retreated, CR or PR were observed in 84.4% and CR in 57.8% of cases. Adverse events, infections, and infusion reactions occurred after first RTX course in 23.8%, 16.4%, and 3.8% of patients and after retreatment in 33.3%, 22.2% and 11.1%, respectively. No severe infusion reactions or deaths occurred. CONCLUSIONS: Data from Italian multicentre RTX Registry confirmed the efficacy and safety of RTX in SLE patients refractory to standard treatment in clinical practice setting.

Management of recurrent thrombosis in antiphospholipid syndrome.

One of the challenges of managing patients with antiphospholipid syndrome is the prevention of rethrombosis (secondary prophylaxis). Risk stratification, i.e. traditional cardiovascular and thrombosis risk factors, systemic autoimmune diseases, antiphospholipid antibody profile, and the intensity of anticoagulation are all relevant to the management of APS patients with recurrent thrombosis. The paper will review "state of the art" strategies for optimizing therapy for APS patients with recurrent thrombosis.

Thrombosis recurrence and major bleeding in non-anticoagulated thrombotic antiphospholipid syndrome patients: Prospective study from antiphospholipid syndrome alliance for clinical trials and international networking (APS ACTION) clinical database and repository ("Registry").

BACKGROUND: Long-term anticoagulant therapy is generally recommended for thrombotic antiphospholipid syndrome (TAPS) patients, however it may be withdrawn or not introduced in routine practice. OBJECTIVES: To prospectively evaluate the risk of thrombosis recurrence and major bleeding in non-anticoagulated TAPS patients, compared to anticoagulated TAPS, and secondly, to identify different features between those two groups. PATIENTS/METHODS: Using an international registry, we identified non-anticoagulated TAPS patients at baseline, and matched them with anticoagulated TAPS patients based on gender, age, type of previous thrombosis, and associated autoimmune disease. Thrombosis recurrence and major bleeding were prospectively analyzed using Kaplan-Meier method and compared using a marginal Cox's regression model. RESULTS: As of June 2022, 94 (14 %) of the 662 TAPS patients were not anticoagulated; and 93 of them were matched with 181 anticoagulated TAPS patients (median follow-up 5 years [interquartile range 3 to 8]). The 5-year thrombosis recurrence and major bleeding rates were 12 % versus 10 %, and 6 % versus 7 %, respectively (hazard ratio [HR] 1.38, 95 % confidence interval [CI] 0.53 to 3.56, p = 0.50 and HR 0.53; 95 % CI 0.15 to 1.86; p = 0.32, respectively). Non-anticoagulated patients were more likely to receive antiplatelet therapy (p < 0.001), and less likely to have more than one previous thrombosis (p < 0.001) and lupus anticoagulant positivity (p = 0.01). CONCLUSION: Fourteen percent of the TAPS patients were not anticoagulated at recruitment. Their recurrent thrombosis risk did not differ compared to matched anticoagulated TAPS patients, supporting the pressing need for risk-stratified secondary thrombosis prevention trials in APS investigating strategies other than anticoagulation.

Management of pregnancy in autoimmune rheumatic diseases: maternal disease course, gestational and neonatal outcomes and use of medications in the prospectiveItalian P-RHEUM.it study.

OBJECTIVES: To investigate pregnancy outcomes in women with autoimmune rheumatic diseases (ARD) in the Italian prospective cohort study P-RHEUM.it. METHODS: Pregnant women with different ARD were enrolled for up to 20 gestational weeks in 29 Rheumatology Centres for 5 years (2018-2023). Maternal and infant information were collected in a web-based database. RESULTS: We analysed 866 pregnancies in 851 patients (systemic lupus erythematosus was the most represented disease, 19.6%). Maternal disease flares were observed in 135 (15.6%) pregnancies. 53 (6.1%) pregnancies were induced by assisted reproduction techniques, 61 (7%) ended in miscarriage and 11 (1.3%) underwent elective termination. Obstetrical complications occurred in 261 (30.1%) pregnancies, including 2.3% pre-eclampsia. Two cases of congenital heart block were observed out of 157 pregnancies (1.3%) with anti-Ro/SSA. Regarding treatments, 244 (28.2%) pregnancies were treated with glucocorticoids, 388 (44.8%) with hydroxychloroquine, 85 (9.8%) with conventional synthetic disease-modifying anti-rheumatic drugs and 122 (14.1%) with biological disease-modifying anti-rheumatic drugs. Live births were 794 (91.7%), mostly at term (84.9%); four perinatal deaths (0.5%) occurred. Among 790 newborns, 31 (3.9%) were small-for-gestational-age and 169 (21.4%) had perinatal complications. Exclusive maternal breast feeding was received by 404 (46.7%) neonates. The Edinburgh Postnatal Depression Scale was compiled by 414 women (52.4%); 89 (21.5%) scored positive for emotional distress. CONCLUSIONS: Multiple factors including preconception counselling and treat-to-target with pregnancy-compatible medications may have contributed to mitigate disease-related risk factors, yielding limited disease flares, good pregnancy outcomes and frequency of complications which were similar to the Italian general obstetric population. Disease-specific issues need to be further addressed to plan preventative measures.

Clinical significance of IgA anti-cardiolipin and IgA anti-ß2glycoprotein I antibodies.

IgA antiphospholipid antibodies (aPL) are not currently recognized as formal laboratory criteria for the Antiphospholipid Syndrome (APS). This is mainly due to methodological issues (different study designs, use of various non-standardized IgA assays). However, there are experimental data showing the pathogenic role of IgA anti-cardiolipin antibodies (aCL) and IgA anti-ß2glycoprotein I antibodies (anti-ß2GPI). Isolated IgA aCL are not very common, therefore their testing could be useful in the case of strong suspicion of APS but negative results for other aPL tests. IgA anti-ß2GPI seem to be the most prevalent isotype in patients with Systemic Lupus Erythematosus (SLE), with a significant association with thrombotic events. Such a clinical relevance has been recently recognized by the inclusion of these autoantibodies among the aPL tests in the novel SLICC classification criteria for SLE. Emerging interest has been raised by IgA anti-ß2GPI against domain 4/5 as a novel subgroup of clinically relevant aPL.

Low complement levels are related to poor obstetric outcomes in women with obstetric antiphospholipid syndrome. The EUROAPS Registry Study Group.

INTRODUCTION: Obstetric antiphospholipid syndrome (OAPS) is an autoimmune disease related to antiphospholipid antibodies (aPL) with primaryinflammatory injury followed by clot cascade activation and thrombus formation. Complement system activation and their participation in aPL-related thrombosis is unclosed. METHODS: We haveanalysed adverse pregnancy outcomes (APO) related to low complement (LC) levels in a cohort of 1048 women fulfilling classification criteria for OAPS. RESULTS: Overall, 223 (21.3%) women presented LC values, during pregnancy. The length of pregnancy was shorter in OAPS women with LC compared to those with normal complement (NC) (median: 33 weeks, interquartile range: [24-38] vs. 35 weeks [27-38]; p = 0.022). Life new-born incidence was higher in patients with NC levels than in those with LC levels (74.4% vs. 67.7%; p = 0.045). Foetal losses were more related to women with triple or double aPL positivity carrying LC than NC values (16.3% vs. 8.0% NC; p = 0.027). Finally, some placental vasculopathies were affected in OAPS patients with LC as late Foetal Growth Restriction (FGR >34 weeks) rise to 7.2% in women with LC vs. 3.2% with NC (p = 0.007). DISCUSSION: Data from our registry indicate that incidence of APO was higher in OAPS women with LC levels and some could be reverted by the correct treatment.