T cell involvement in antiphospholipid syndrome.

Antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized by arterial and venous thrombosis, and obstetric complications in the presence of antiphospholipid antibodies (aPL), including lupus anticoagulant, anticardiolipin and anti-ß2-glycoprotein I antibodies. APS manifests as single, often as recurrent events, and rarely as a catastrophic condition. Most studies of APS pathogenesis to date have focused on the prothrombotic role of aPL, while innate immune responses such as monocyte, complement and neutrophil activation have been also recognized as part of the thrombo-inflammatory cascade in APS. While the presence of autoreactive T cells against ß2-glycoprotein I has been long known, less data are available on their pathogenetic role in APS. In this review, we summarize current knowledge on the involvement of T cells in APS pathophysiology, alterations of T cell subsets in peripheral blood, and clinical associations. We also highlight potential therapeutic opportunities by targeting T helper-B cell interactions in these patients.

EULAR recommendations for the management of systemic lupus erythematosus: 2023 update.

OBJECTIVES: To update the EULAR recommendations for the management of systemic lupus erythematosus (SLE) based on emerging new evidence. METHODS: An international Task Force formed the questions for the systematic literature reviews (January 2018-December 2022), followed by formulation and finalisation of the statements after a series of meetings. A predefined voting process was applied to each overarching principle and recommendation. Levels of evidence and strengths of recommendation were assigned, and participants finally provided their level of agreement with each item. RESULTS: The Task Force agreed on 5 overarching principles and 13 recommendations, concerning the use of hydroxychloroquine (HCQ), glucocorticoids (GC), immunosuppressive drugs (ISDs) (including methotrexate, mycophenolate, azathioprine, cyclophosphamide (CYC)), calcineurin inhibitors (CNIs, cyclosporine, tacrolimus, voclosporin) and biologics (belimumab, anifrolumab, rituximab). Advice is also provided on treatment strategies and targets of therapy, assessment of response, combination and sequential therapies, and tapering of therapy. HCQ is recommended for all patients with lupus at a target dose 5 mg/kg real body weight/day, considering the individual's risk for flares and retinal toxicity. GC are used as 'bridging therapy' during periods of disease activity; for maintenance treatment, they should be minimised to equal or less than 5 mg/day (prednisone equivalent) and, when possible, withdrawn. Prompt initiation of ISDs (methotrexate, azathioprine, mycophenolate) and/or biological agents (anifrolumab, belimumab) should be considered to control the disease and facilitate GC tapering/discontinuation. CYC and rituximab should be considered in organ-threatening and refractory disease, respectively. For active lupus nephritis, GC, mycophenolate or low-dose intravenous CYC are recommended as anchor drugs, and add-on therapy with belimumab or CNIs (voclosporin or tacrolimus) should be considered. Updated specific recommendations are also provided for cutaneous, neuropsychiatric and haematological disease, SLE-associated antiphospholipid syndrome, kidney protection, as well as preventative measures for infections, osteoporosis, cardiovascular disease. CONCLUSION: The updated recommendations provide consensus guidance on the management of SLE, combining evidence and expert opinion.

Epidemiology of antiphospholipid syndrome: macro- and microvascular manifestations.

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by thrombotic and non-thrombotic macro- and microvascular manifestations and pregnancy complications in the setting of persistent antiphospholipid antibodies (aPL), namely anticardiolipin antibodies, anti-ß2 glycoprotein-I antibodies and lupus anticoagulant. Four decades after its first description, APS prevalence and incidence are still not completely understood due to the limited number of well-designed, population-based multi-ethnic studies. Furthermore, despite decades of efforts to standardise aPL immunoassays, considerable intraassay and interlaboratory variances in aPL measures still exist. Large multicentre APS cohorts have shown a 10-year survival of ∼91% and the presence of catastrophic APS occurs in about 1% of the entire population, associated with a 50% mortality rate. Clinically, any organ can be affected in the context of large, medium or small vessel (artery and/or vein) thrombosis. Macrovascular thrombosis is the hallmark of the disease and veins are more frequently affected than arteries. Deep vein thrombosis/pulmonary embolism thromboembolic disease is the most common APS manifestation, while stroke and transient ischaemic attack are the most frequent arterial thrombosis events. Myocardial infarction can also occur and contributes to increased mortality in APS. A minority of patients present with thrombosis affecting the intraabdominal organs, including the liver, spleen, small and large bowel, and the kidneys. Microvascular thrombosis, including APS nephropathy, chronic skin ulcers and livedoid vasculopathy represent a diagnostic challenge requiring histologic confirmation. In this narrative review we summarize the available evidence on APS epidemiology, focusing on the description of the prevalence of macro- and microvascular manifestations of the disease.

Anticoagulant and non-anticoagulant therapy in thrombotic antiphospholipid syndrome: old drugs and new treatment targets.

In this review, we discuss the current evidence on classic and newer oral anticoagulant therapy, older drugs such as HCQ and statins, and new potential treatment targets in APS. Vitamin K antagonists (VKAs) remain the cornerstone treatment for thrombotic events in APS. In patients fulfilling criteria for definite APS presenting with a first venous thrombosis, treatment with VKAs with a target international normalized ratio (INR) 2.0-3.0 is recommended. In patients with arterial thrombosis, treatment with VKA with target INR 2.0-3.0 or 3.0-4.0 is recommended by recent guidelines, considering the individual's bleeding and thrombosis recurrence risk. A combination of VKAs and low-dose aspirin (75-100 mg/daily) may also be considered. According to available evidence direct oral anticoagulants should be avoided in patients with arterial thrombosis and/or those with triple aPL positivity. Adjunctive treatment with HCQ and/or statins can be considered, especially in anticoagulation treatment-refractory APS. Potential targeted treatments in APS include B-cell targeting, complement inhibition, mammalian target of rapamycin inhibition, IFN targeting, adenosine receptors agonists, CD38 targeting or chimeric antigen receptor T-cell therapy. The safety and efficacy of these treatment targets needs to be examined in well-designed randomized controlled trials.

Arterial stiffness tested by pulse wave velocity and augmentation index for cardiovascular risk stratification in antiphospholipid syndrome.

OBJECTIVES: Cardiovascular disease is a major cause of morbidity and mortality in Antiphospholipid syndrome (APS). Arterial stiffness (ArS) has emerged as a predictor of future cardiovascular events in the general population. We aimed to assess ArS in patients with thrombotic APS versus diabetes mellitus (DM) and healthy controls (HC) and identify predictors of increased ArS in APS. METHODS: ArS was evaluated by carotid-femoral pulse wave velocity (cfPWV) and augmentation index normalized to 75 beats/min (AIx@75) using the SphygmoCor device. Participants also underwent carotid/femoral ultrasound for atherosclerotic plaque detection. We used linear regression to compare ArS measures among groups and assess ArS determinants in the APS group. RESULTS: We included 110 patients with APS (70.9% female, mean age 45.4 years), 110 DM patients and 110 HC, all age/sex matched. After adjustment for age, sex, cardiovascular risk factors and plaque presence, APS patients exhibited similar cfPWV [ß = -0.142 (95% CI -0.514, 0.230), p = 0.454] but increased AIx@75 [ß = 4.525 (95% CI 1.372, 7.677), p = 0.005] compared with HC and lower cfPWV (p < 0.001) but similar AIx@75 (p = 0.193) versus DM patients. In the APS group, cfPWV was independently associated with age [ß = 0.056 (95% CI 0.034, 0.078), p < 0.001], mean arterial pressure (MAP) [ß = 0.070 (95% CI 0.043, 0.097), p < 0.001], atherosclerotic femoral plaques [ß = 0.732 (95% CI 0.053, 1.411), p = 0.035] and anti-ß2-glycoprotein I IgM positivity [ß = 0.696 (95% CI 0.201, 1.191), p = 0.006]. AIx@75 was associated with age [ß = 0.334 (95% CI 0.117, 0.551), p = 0.003], female sex [ß = 7.447 (95% CI 2.312, 12.581), p = 0.005] and MAP [ß = 0.425 (95% CI 0.187, 0.663), p = 0.001]. CONCLUSION: APS patients exhibit elevated AIx@75 vs HC and similar to DM patients, indicating enhanced arterial stiffening in APS. Given its prognostic value, ArS evaluation may help to improve cardiovascular risk stratification in APS.

The impact of traditional cardiovascular risk factor control on 7-year follow-up atherosclerosis progression in systemic lupus erythematosus.

OBJECTIVES: The 2022 EULAR recommendations for cardiovascular risk management in patients with rheumatic disorders, including SLE, call for rigorous management of cardiovascular risk factors (CVRF). The impact of CVRF target attainment on atherosclerotic plaque progression hasn't been previously evaluated in prospective ultrasound studies. METHODS: A total of 115 patients with SLE and 1:1 age and sex-matched healthy controls who had a baseline carotid and femoral ultrasound examination in our cardiovascular research unit were invited for a 7-year follow-up assessment of new plaque development. We aimed to compare the incidence of plaque progression between SLE patients and controls and reveal the extent to which it is affected by the attainment of European Society of Cardiology (ESC) targets for modifiable CVRFs (blood pressure, smoking status, body weight, lipids and physical activity), and disease-related features (disease duration, disease activity, autoantibodies, treatments). RESULTS: Eighty-six SLE patients and 42 controls had a 7-year follow-up carotid and femoral plaque examination. New plaque development was observed in 32/86 patients vs 8/42 controls (P = 0.037). Patients with SLE had a 4-fold higher risk for plaque progression than controls (OR: 4.16, CI: 1.22, 14.19, P = 0.023), adjusting for potential confounders. Multivariate regression analyses showed a 50% decrease in plaque progression for every modifiable CVRF fulfilling ESC targets (OR: 0.56, CI: 0.34, 0.93, P = 0.026). CONCLUSION: Patients with SLE develop a rapid progression of atherosclerotic plaques which may be drastically reduced by CVRF target attainment according to ESC guidelines.

7-year follow-up atherosclerotic plaque progression in patients with antiphospholipid syndrome versus diabetes mellitus and healthy controls.

OBJECTIVES: Patients with antiphospholipid syndrome (APS) carry a substantial burden of cardiovascular disease and subclinical atherosclerosis. We aimed to assess a 7-year follow-up atherosclerotic plaque progression in APS patients vs diabetes mellitus (DM) and healthy controls (HC). METHODS: Eighty-six patients with thrombotic APS, 86 with DM and 86 HC (all age- and sex-matched) who underwent a baseline ultrasound of carotid and femoral arteries were invited for a 7-year follow-up ultrasonography examination. We compared atherosclerosis progression among the three groups and examined determinants of plaque progression in APS patients. RESULTS: Sixty-four APS patients (75% females, 43.8% with primary APS), 58 patients with DM and 66 HC were included in the 7-year ultrasound re-evaluation. New plaque was detected in 51.6%, 36.2% and 25.8% of APS, DM and HC subjects, respectively. After adjusting for traditional cardiovascular risk factors (CVRFs) and baseline plaque presence, APS patients showed a 3-fold (OR = 3.07, p= 0.007) higher risk for atherosclerosis progression vs HC and 2-fold (OR = 2.25, p= 0.047) higher risk than DM patients. In multivariate analysis in the APS group, plaque progression was independently associated with systemic lupus erythematosus (SLE) co-existence (OR = 7.78, p= 0.005) and number of CVRFs (OR = 3.02, p= 0.002), after adjusting for disease-related parameters and CVRF-related medications. Sustained low-density lipoprotein target attainment reduced plaque progression risk (OR = 0.34, p= 0.021). CONCLUSION: Half of APS patients develop new atherosclerotic plaques over a 7-year follow-up, having a three-times higher risk vs HC. Concomitant SLE and number of traditional CVRFs are associated with plaque progression, supporting the need for thorough CVRF assessment and control.

Outcomes of COVID-19 Omicron variant in patients with rheumatoid arthritis: a nationwide Greek cohort study.

OBJECTIVES: Patients with RA were at increased risk for COVID-19-associated hospitalization and death during the first year of the pandemic in Greece. We aimed to examine their outcomes after the SARS-Cov-2 Omicron, a more contagious but with milder clinical impacts variant, prevailed. METHODS: A retrospective, nationwide study was conducted between 1 January 2022 and 30 June 2022 in all RA patients under treatment and matched (1:5) on age, sex and region of domicile random general population comparators. Confirmed SARS-CoV-2 infections, hospitalizations and deaths, anti-rheumatic medications, prior COVID-19, vaccinations and anti-viral medications were recorded. RESULTS: Among 34 182 RA patients, infections (n = 5569, 16.29%), hospitalizations (n = 489, 1.43%) and deaths (n = 106, 0.31%) were more frequent than among comparators. Incidence rates per 1000 person/years of infection [IRR (95% CI):1.19 (1.16, 1.23)], hospitalization [IRR (95% CI):2.0 (1.82, 2.24)], and death [IRR (95% CI):1.81 (1.44, 2.27)] were increased in RA despite better vaccination coverage (89% vs 84%) and more frequent use of anti-viral medications (2.37% vs 1.08). Logistic regression analysis after correcting for age, sex, vaccinations, prior COVID-19, and anti-viral medications in SARS-CoV-2 infected RA patients and comparators revealed increased risk of hospitalization (OR: 2.02, 95% CI: 1.79, 2.27) and death [OR: 1.73, (95% CI: 1.36, 2.20)] in RA. Among infected RA patients, rituximab treatment conferred increased risks for hospitalization [OR: 6.12, (95% CI: 2.89, 12.92)] and death [OR: 12.06 (95% CI: 3.90, 37.31)], while JAK inhibitors increased only hospitalization risk [OR: 2.18 (95% CI: 1.56, 3.06)]. CONCLUSION: RA remains a risk factor for hospitalization and death in an era of a relatively low COVID-19 fatality rate, pointing to the need of perseverance in vaccination programs and wider use of anti-viral medications.

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.

Identification and characteristics of patients with potential difficult-to-treat Psoriatic Arthritis: exploratory analyses of the Greek PsA registry.

OBJECTIVE: To present the characteristics of patients with potential difficult-to-treat (D2T) psoriatic arthritis (PsA). METHODS: We used data from the Greek multicentre registry of PsA patients. D2T-PsA was defined as follows: patients with at least 6-months disease duration, who have failed to at least 1 csDMARD and at least 2 bDMARDs/tsDMARDs with a different mechanism of action and have either at least moderate disease activity (MODA) defined as DAPSA > 14, and/or are not at minimal disease activity (MDA). Demographic and clinical characteristics were compared between D2T and non-D2T PsA patients. In two sensitivity analyses, patients classified as D2T solely according to the MODA or MDA criterion were examined separately. RESULTS: Among 467 patients included, 77 (16.5%) were considered D2T and 390 non-D2T PsA. Compared with non-D2T, patients with D2T PsA presented more commonly with extensive psoriasis (p< 0.0001) and were more likely to have higher BMI (p= 0.023) and a history of inflammatory bowel disease (p= 0.026). In the MODA and MDA sensitivity analyses, 7.5% and 12.5% of patients were considered D2T, respectively. In both sensitivity analyses, extensive psoriasis was again identified as an independent variable for D2T PsA (p= 0.001 and p= 0.008, respectively). Moreover, female gender (p= 0.034) in the MODA analysis and axial disease (p= 0.040) in the MDA analysis were independent variables for D2T PsA. CONCLUSION: Despite the availability of therapies, D2T PsA is common in real-life cohorts of patients with PsA and extensive psoriasis. High BMI, female gender, axial-disease, and history of IBD were also associated with D2T PsA.

Efforts to Better Characterize "Antiphospholipid Antibody Nephropathy" for the 2023 ACR/EULAR Antiphospholipid Syndrome Classification Criteria: Renal Pathology Subcommittee Report.

OBJECTIVE: Antiphospholipid antibody (aPL) nephropathy (-N) can be challenging to recognize due to a lack of established classification or diagnostic criteria. As part of efforts to develop new antiphospholipid syndrome (APS) classification criteria (CC), the APS CC Renal Pathology Subcommittee aimed to better characterize the entity of aPL-N. METHODS: We used a 4-pronged approach that included (1) administering Delphi surveys to worldwide APS physicians to generate aPL-N terminology; (2) conducting a literature review to demonstrate the association of nephropathy with aPL and identify published aPL-N histopathological terminology and descriptions; (3) evaluating aPL-N terminology used in renal biopsy reports from an international patient registry; and (4) evaluating proposed kidney pathologic features for aPL-N by assessment of international Renal Pathology Society (RPS) members. RESULTS: After completing our metaanalysis demonstrating an association between nephropathy and aPL, we used Delphi surveys, a literature review, and international renal biopsy reports to develop a preliminary definition of aPL-N. The preliminary definition included include specific terms associated with acute (ie, thrombotic microangiopathy in glomeruli or arterioles/arteries) and chronic (ie, organized arterial or arteriolar microthrombi with or without recanalization, organized glomerular thrombi, fibrous and fibrocellular [arterial or arteriolar] occlusions, focal cortical atrophy with or without thyroidization, and fibrous intimal hyperplasia) lesions. Most RPS survey respondents agreed with this terminology and the importance of knowing aPL results for histopathological diagnosis. CONCLUSION: Our results support the inclusion of aPL-N in the 2023 American College of Rheumatology/European Alliance of Associations for Rheumatology APS CC, and provide the most widely accepted terminology to date for both acute and chronic pathologic lesions of aPL-N.

Outcomes of COVID-19 re-infections: a single-center cohort of 167 patients with systemic rheumatic diseases.

Data on COVID-19 re-infections in patients with systemic rheumatic diseases (SRDs) are lacking. We aimed to describe the course and outcomes of COVID-19 re-infections in these patients versus controls. In this single-center retrospective study, we included 167 consecutive SRD patients with at least one COVID-19 re-infection (mean age 47.3 years, females 70.7%). SRD patients were compared in terms of patient-perceived COVID-19 re-infection severity and hospitalizations/deaths with 167 age/sex-matched non-SRD controls. Logistic regression analysis was performed to assess potential milder re-infection versus primary infection severity, adjusting for study group, demographics (age, sex), vaccination status, body mass index, smoking, and comorbidities. 23 and 7 out of 167 re-infected SRD patients experienced two and three re-infections, respectively, which were comparable to the re-infection rates in controls (two: 32; and three: 2) who also had comparable COVID-19 vaccination history (89% and 95% vaccinated, respectively). In the initial infection, patients with SRDs were hospitalized (7.2% versus 1.8%, p = 0.017), and had received antiviral treatment (16.1% versus 4.7%, p < 0.001) more frequently than controls. However, hospitalizations (1.8% vs 0.6%) and antiviral treatment (7.8% vs 3.5%) did not differ (p > 0.05) between patients and controls at the first re-infection, as well as during the second and third re-infection; no deaths were recorded. Perceived severity of re-infections was also comparable between patients and controls (p = 0.847) and among those on biologic DMARDs or not (p = 0.482). In multivariable analysis, neither SRDs presence nor demographics or comorbidities were associated with COVID-19 re-infection severity. COVID-19 re-infection severity (patient-perceived/hospitalizations/deaths) did not differ between SRDs and controls.

Glucocorticoid discontinuation rate and risk factors for relapses in a contemporary cohort of patients with giant cell arteritis.

The rates of relapses and therapy discontinuation in patients with giant cell arteritis (GCA) in the modern therapeutic era have not been defined. We aimed to evaluate the glucocorticoid (GC) discontinuation rate and the factors associated with relapses in a contemporary GCA cohort. Patient and treatment data were collected cross-sectionally at first evaluation and 2 years later (second evaluation), in a multicenter, prospective GCA cohort. Predictors of relapses were identified by logistic regression analyses. 243 patients with GCA were initially included (67% women, mean age at diagnosis: 72.1 years, median disease duration: 2 years) while 2 years later complete data for 160 patients were available and analyzed. All patients had received GCs at diagnosis (mean daily prednisolone dose: 40 mg) while during follow-up, 37% received non-biologic and 16% biologic agents, respectively. At second evaluation, 72% of patients were still on therapy (GCs: 58% and/or GC-sparing agents: 29%). Relapses occurred in 27% of patients during follow-up; by multivariable logistic regression analysis, large vessel involvement at diagnosis [odds ratio (OR) = 4.22], a cardiovascular event during follow-up (OR = 4.60) and a higher initial GC daily dose (OR = 1.04), were associated with these relapses. In this large, real-life, contemporary GCA cohort, the rates of GC discontinuation and relapses were 40% and 27%, respectively. Large vessel involvement, a higher GC dose at diagnosis and new cardiovascular events during follow-up were associated with relapses.

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.

Antiphospholipid syndrome nephropathy: Current knowledge and unanswered questions.

The definition of acute and chronic antiphospholipid syndrome (APS) nephropathy was recently updated using a multiphase methodology in the context of the development of the new APS classification criteria. Currently, there is no consensus for the treatment of APS nephropathy, which mainly relies on the general recommendations for the management of APS. Based on evidence from experimental studies and a few clinical studies and case series, targeted treatments such as B-cell depletion, anti-B-cell activating factor antibody, complement inhibition, mammalian target of rapamycin inhibition, and neutrophil extracellular traps or interferon targeting may show promise for the treatment of microvascular manifestations in APS, including APS nephropathy. Validation of the new APS nephropathy definition and/or efforts for improvement in proposed terminology, along with the assessment of the safety and efficacy of potential targeted treatments in randomized controlled trials, are major future research directions. In this review, we summarize the current knowledge of APS nephropathy and discuss unanswered questions.

Assessing disease activity and damage in antiphospholipid syndrome.

Antiphospholipid syndrome (APS) has been characterized by a variety of vascular and pregnancy manifestations related to an interplay between thrombotic and inflammatory mechanisms, a progressive accrual of irreversible organ damage and increased morbidity and mortality rates, supporting a high need of optimal treatment approach. The lack of standardized outcome measures is a significant barrier in the design of clinical studies in APS. Disease activity (in principle reversible) and its distinction from disease damage (in principle irreversible) needs to be evaluated by validated scores for use in clinical trials but also in daily clinical practice in APS. A disease damage score in APS, the DIAPS score, has been developed and validated in external cohorts. The development of a disease activity score that will provide an accurate and reproducible rating of each disease domain, can help clinicians and researchers to comprehensively assess the activity of disease and the response to treatment, in an attempt to prevent future damage.

Augmented oxidative stress, accumulation of DNA damage and impaired DNA repair mechanisms in thrombotic primary antiphospholipid syndrome.

Antiphospholipid syndrome (APS) is a rare autoimmune disorder with complex pathogenesis. Studies have shown that oxidative stress may contribute to APS pathophysiology. In peripheral blood mononuclear cells (PBMCs) from thrombotic Primary APS (thrPAPS) patients and age/sex-matched healthy controls (HC), as well as a control group of asymptomatic antiphospholipid antibody (aPL) positive individuals without APS (aPL+/non-APS), we examined oxidative stress, abasic (apurinic/apyrimidinic) sites, and DNA damage response (DDR)-associated parameters, including endogenous DNA damage (single- and double-strand breaks) and DNA repair mechanisms, namely nucleotide excision repair (NER) and double-strand breaks repair (DSB/R). We found that thrPAPS patients exhibited significantly higher levels of endogenous DNA damage, increased oxidative stress and abasic sites, as well as lower NER and DSB/R capacities versus HC (all P < 0.001) and versus aPL+/non-APS subjects (all P < 0.05). Our findings demonstrate that oxidative stress and decreased DNA repair mechanisms contribute to the accumulation of endogenous DNA damage in PBMCs from thrPAPS patients and, if further validated, may be exploited as therapeutic targets and potential biomarkers.

Distinct innate and adaptive immunity phenotypic profile at the circulating single-cell level in Psoriatic Arthritis.

Mass cytometry was employed to investigate 47 circulating leukocyte subsets in patients with active psoriatic arthritis (PsA, n = 16) compared to healthy controls (n = 13), seropositive (RF and/or anti-CCP, n = 12) and seronegative (n = 9) RA patients. Comparing PsA to controls, different cell frequencies were found in both innate and adaptive immunity cell subsets, as well as in cells bridging innate and adaptive immunity. In some T cell subsets increased costimulatory molecules' expression in PsA, was also noted.No changes were observed in patients who remained disease-active after 3 months of treatment, in contrast to those who achieved remission/low-disease activity. Comparing PsA to seropositive RA, elevated frequencies of naïve and activated CD8+ T cells, B cells, MAIT/iNKT and ILCs were found, while the opposite was the case for terminal effector, senescent, and Th2-like cells. Strikingly, the composition of the leukocyte pool in PsA was comparable to seronegative RA, providing evidence for the pathogenetic similarities between these two entities.

Whole blood transcriptome identifies interferon-regulated genes as key drivers in thrombotic primary antiphospholipid syndrome.

OBJECTIVE: Pathogenesis of antiphospholipid syndrome (APS) isn't fully elucidated. We aimed to identify gene signatures characterizing thrombotic primary APS (thrPAPS) and subgroups at high risk for worse outcomes. METHODS: We performed whole blood next-generation RNA-sequencing in 62 patients with thrPAPS and 29 age-/sex-matched healthy controls (HCs), followed by differential gene expression analysis (DGEA) and enrichment analysis. We trained models on transcriptomics data using machine learning. RESULTS: DGEA of 12.306 genes revealed 34 deregulated genes in thrPAPS versus HCs; 33 were upregulated by at least 2-fold, and 14/33 were type I and II interferon-regulated genes (IRGs) as determined by interferome database. Machine learning applied to deregulated genes returned 79% accuracy to discriminate thrPAPS from HCs, which increased to 82% when only the most informative IRGs were analyzed. Comparison of thrPAPS subgroups versus HCs showed an increased presence of IRGs among upregulated genes in venous thrombosis (21/23, 91%), triple-antiphospholipid antibody (aPL) positive (30/50, 60%), and recurrent thrombosis (19/42, 45%) subgroups. Enrichment analysis of upregulated genes in triple-aPL positive patients revealed terms related to 'type I interferon signaling pathway' and 'innate immune response'. DGEA among thrPAPS subgroups revealed upregulated genes, including IRGs, in patients with venous versus arterial thrombosis (n = 11, 9 IRGs), triple-aPL versus non-triple aPL (n = 10, 9 IRGs), and recurrent versus non-recurrent thrombosis (n = 10, 3 IRGs). CONCLUSION: Upregulated IRGs may better discriminate thrPAPS from HCs than all deregulated genes in peripheral blood. Taken together with DGEA data, IRGs are highly expressed in thrPAPS and high-risk subgroups of triple-aPL and recurrent thrombosis, with potential treatment implications.

Different COVID-19 outcomes among systemic rheumatic diseases: a nation-wide cohort study.

OBJECTIVES: To investigate coronavirus disease 2019 (COVID-19)-associated risk of hospitalization and death in RA, AS, PsA, SLE and SSc in comparison with the general population during the first year of the pandemic, and compare their overall mortality with 2019. METHODS: Interlinking nationwide electronic registries, we recorded confirmed COVID-19-associated infections, hospitalizations and deaths, and all-cause deaths between 1 March 2020 and 28 February 2021 in all adults with RA, AS, PsA, SLE and SSc under treatment (n = 74 970, median age 67.5, 51.2, 58.1, 56.2 and 62.2 years, respectively) and in random comparators from the general population matched (1:5) on age, sex and region of domicile. Deaths from all causes during 2019 were also recorded. RESULTS: Compared with the general population, incidence rates (IR) for COVID-19-associated hospitalization were higher in RA [IR ratio (IRR) 1.71(1.50-1.95)], SLE [2.0 (1.4-2.7)] and SSc [2.28 (1.29-3.90)], while COVID-19-associated death rates were higher in RA [1.91 (1.46-2.49)]. When focusing only on severe acute respiratory syndrome coronavirus 2-infected subjects, after adjusting for age and gender, the odds ratio for COVID-19 associated death was higher in RA [1.47 (1.11-1.94)] and SSc [2.92 (1.07-7.99)] compared with the general population. The all-cause mortality rate compared with the general population increased in RA during the first year of the pandemic (IRR 0.71) with reference to 2019 (0.59), and decreased in SSc (IRR 1.94 vs 4.36). CONCLUSION: COVID-19 may have a more severe impact in patients with systemic rheumatic disease than in the general population. COVID-19-related mortality is increased in subgroups of patients with specific rheumatic diseases, underscoring the need for priority vaccination and access to targeted treatments.