Assessment of the 2023 ACR/EULAR antiphospholipid syndrome classification criteria in a Chinese cohort: Impact on clinical practice.

OBJECTIVES: To evaluate the effectiveness of the 2023 ACR/EULAR criteria for antiphospholipid syndrome (APS) in a Chinese cohort, and compare them with the Sapporo and revised Sapporo criteria. METHODS: A cohort comprising 436 patients diagnosed with APS and 514 control subjects was enrolled, including 83 with seronegative APS and 86 classified as antiphospholipid antibody (aPL) carriers. We assessed IgG and IgM anticardiolipin antibodies (aCL) and anti-ß2-glycoprotein I (aß2GPI) antibodies using ELISA, along with a systematic collection of lupus anticoagulant data. Subsequently, we compared the sensitivity and specificity across the three classification criteria. RESULTS: The 2023 ACR/EULAR criteria exhibited improved specificity at 98 %, surpassing the revised Sapporo (90 %) and original Sapporo (91 %) criteria. However, this came with decreased sensitivity at 82 %, in contrast to higher sensitivities in the revised Sapporo (98 %) and Sapporo (91 %) criteria. Examining individual components sheds light on the scoring system's rationale within the new criteria. The inclusion of microvascular thrombosis, cardiac valve disease, and thrombocytopenia improved the identification of nine patients previously classified as "probable APS". Insufficient scoring in 78 previously diagnosed APS individuals was linked to traditional risk factor evaluations for thrombotic events, the emphasis on determining whether obstetric events are linked to severe preeclampsia (PEC) or placental insufficiency (PI), and the lower scores assigned to IgM aCL and/or aß2GPI antibody. Seronegative APS remained a challenge, as non-criteria aPL and other methods were not included. CONCLUSIONS: The new criteria presented notable advancements in specificity. This study provides detailed insights into the strengths and possible challenges of the 2023 ACR/EULAR criteria, enhancing our understanding of their impact on clinical practice.

Neutrophil activation biomarker pentraxin 3 for diagnosis and monitoring of macrophage activation syndrome occurrence in adult-onset Still's disease.

Macrophage activation syndrome (MAS) is a potentially fatal consequence of adult-onset Still's disease (AOSD), driven by a cytokine storm. Efficient early diagnosis of AOSD-associated MAS requires a sensitive and specific biomarker. In this study, we demonstrated that pentraxin 3 (PTX3), an acute phase protein, was associated with AOSD disease activity and served as a biomarker for AOSD-MAS. PTX3 levels were significantly increased in AOSD patients compared to other autoimmune diseases and healthy controls. Plasma PTX3 levels showed positive correlations with inflammatory markers, the systemic score and the HScore. In active AOSD with MAS, PTX3 levels were higher compared to those in non-AOSD haemophagocytic lymphohistiocytosis (HLH) patients. Moreover, the PTX3's area under the curve value for distinguishing AOSD with MAS exceeded that of soluble interleukin-2 receptor, ferritin and C-reactive protein. Furthermore, plasma levels of PTX3 were associated with circulating NET-DNA levels. To fully understand the underlying mechanism of PTX3 prompting AOSD and AOSD-MAS progression, we discovered that neutrophils exhibited enhanced NET formation and mitogen-activated protein kinases (MAPK) pathway activation upon PTX3 stimulation. More importantly, PTX3-induced NET formation was effectively dampened by MAPK pathway inhibitors. These findings collectively revealed that PTX3 has a favorable correlation with disease activity and may serve as a potential biomarker to differentiate AOSD patients with MAS. Additionally, PTX3 induces NET release via the MAPK pathway, suggesting a pathogenic role in AOSD-MAS.

Activation of Platelet mTORC2/Akt Pathway by Anti-ß2GP1 Antibody Promotes Thrombosis in Antiphospholipid Syndrome.

BACKGROUND: Anti-ß2GP1 (ß2-glycoprotein 1) antibodies are the primary pathogenic antibody to promote thrombosis in antiphospholipid syndrome (APS), yet the underlying mechanism remains obscure. We aimed to explore the intracellular pathway that mediated platelet activation. METHODS: Platelets were isolated from patients with APS and subjected to RNA sequencing. Platelet aggregation, the release of platelet granules, platelet spreading, and clot retraction were detected to evaluate platelet activation. We purified anti-ß2GP1 antibodies from patients with APS and the total IgG from healthy donors to stimulate platelets with/without FcγRIIA (Fcγ receptor IIA) blocking antibody or Akt (protein kinase B) inhibitor. Platelet-specific Sin1 (stress-activated protein kinase-interacting protein) deficiency mice were established. The thrombus model of inferior vena cava flow restriction, ferric chloride-induced carotid injury model, and laser-induced vessel wall injury in cremaster arterioles model were constructed after administration of anti-ß2GP1 antibodies. RESULTS: Combined RNA sequencing and bioinformatics analysis suggested that APS platelets exhibited increased levels of mRNA associated with platelet activation, which was in line with the hyperactivation of APS platelets in response to stimuli. Platelet activation in APS platelets was accompanied by upregulation of the mTORC2 (mammalian target of the rapamycin complex 2)/Akt pathway and increased levels of SIN1 phosphorylation at threonine 86. Anti-ß2GP1 antibody derived from patients with APS enhanced platelet activation and upregulated the mTORC2/Akt pathway. Moreover, the Akt inhibitor weakened the potentiating effect of the anti-ß2GP1 antibody on platelet activation. Notably, Sin1 deficiency suppresses anti-ß2GP1 antibody-enhanced platelet activation in vitro and thrombosis in all 3 models. CONCLUSIONS: This study elucidated the novel mechanism involving the mTORC2/Akt pathway, which mediates the promotion of platelet activation and induction of thrombosis by the anti-ß2GP1 antibody. The findings suggest that SIN1 may be a promising therapeutic target for the treatment of APS.

Risk factors in antiphospholipid antibody-associated valvular heart disease: A 383-patient cohort study.

Valvular heart disease (VHD) is a prevalent cardiac manifestation in antiphospholipid syndrome (APS) patients. However, risk factors and predictors for antiphospholipid antibody-associated VHD (aPL-VHD) remain vague. We aimed to assess the risk of developing aPL-VHD in aPL-positive patients, by establishing a clinical prediction model upon a cross-sectional cohort from APS-Shanghai database, including 383 APS patients and durable aPL carriers with transthoracic echocardiography investigation. The prevalence of aPL-VHD was 11.5%. Multivariate logistic regression analysis identified three independent risk factors for aPL-VHD: anti-ß2GPI IgG (OR 5.970, P < 0.001), arterial thrombosis (OR 2.758, P = 0.007), and stratified estimated glomerular filtration rate levels (OR 0.534, P = 0.001). A prediction model for aPL-VHD, incorporating the three factors, was further developed, which demonstrated good discrimination with a C-index of 0.855 and 0.841 (after bootstrapping), and excellent calibration (P = 0.790). We provide a practical tool for assessing the risk of developing VHD among aPL-positive patients.

Neutrophil extracellular trap-induced intermediate monocytes trigger macrophage activation syndrome in adult-onset Still's disease.

BACKGROUND: Adult-onset Still's disease (AOSD) is a systemic autoinflammatory disease characterized by innate immune system activation, with a high risk for macrophage activation syndrome (MAS). MAS development is associated with monocyte/macrophage activation and cytokine storm. Monocytes consist of three different subsets, classical monocytes (CMs, CD14brightCD16 -), intermediate monocytes (IMs, CD14brightCD16 +), and non-classical monocytes (NCMs, CD14dimCD16 +), each has distinct roles in inflammatory regulation. However, the frequencies and regulatory mechanism of monocyte subsets in AOSD patients have not been identified. METHODS: We performed flow cytometry, RNA sequencing, phagocytosis analysis, and enzyme-linked immunosorbent assay to evaluate monocyte subsets, cell functions, and potential biomarkers. The effect of neutrophil extracellular traps (NETs) on monocytes was determined by evaluating mRNA levels of DNA sensors, surface CD16 expression, and inflammasome pathway activation. RESULTS: Higher proportions of intermediate monocytes (IMs) were identified in active AOSD patients. IMs displayed higher expression of CD80, CD86, HLA-DR, and CD163 than CMs and NCMs. CD163 upregulation was noted on AOSD IMs, accompanied by increased phagocytic activity and elevated cytokine/chemokine production, including IL-1ß, IL-6, CCL8, and CXCL10. The frequencies of IMs were correlated with disease activity and higher in AOSD patients with MAS (AOSD-MAS). CCL8 and CXCL10 were highly expressed in RNA sequencing of monocytes from AOSD-MAS patients and plasma CXCL10 level could serve as a potential biomarker for AOSD-MAS. Moreover, DNA-sensing pathway was activated in monocytes from AOSD-MAS patients. Stimulation with NETs derived from AOSD induced DNA sensor expression, the expansion of IMs, and inflammasome pathway activation. These effects can be abrogated by DNase I treatment. CONCLUSIONS: Our results demonstrated that the proportions of IMs were elevated in AOSD and associated with MAS. The DNA component in NETs from AOSD plays an important role in the formation of IMs, shedding new light for the therapeutic target.

Inactivated SARS-CoV-2 vaccine does not increase the risk of relapse in patients with clinically inactive adult-onset Still's disease.

OBJECTIVE: A succession of cases have reported flares of adult-onset Still's disease (AOSD) after vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), raising concerns. We aimed to investigate the impact of inactivated SARS-CoV-2 vaccines on disease activity in patients with AOSD. METHODS: We prospectively enrolled clinically inactive AOSD patients visiting the outpatient clinics of our department. The patients received SARS-CoV-2 vaccines (BBIBP-CorV, Sinopharm, Beijing, China) voluntarily. The occurrence of relapse in the participants was recorded during the follow-up period, and a propensity score matching (PSM) method was used to compare the relapse rates between vaccinated and unvaccinated patients. Localized and systemic symptoms were assessed in the vaccinated patients. RESULTS: A total of 122 patients with inactive AOSD were included, of which 49.2% (n = 60) voluntarily received the inactivated SARS-CoV-2 vaccine. The relapse rate did not increase significantly in vaccinated patients in comparison with unvaccinated patients (after PSM: 6.8% vs 6.8%), and no relapse occurred within 1 month after vaccination. No obvious adverse reactions were reported in 75.0% of the participants, and none of the patients reported severe reactions. CONCLUSION: Increased disease activity or relapse following vaccination with inactivated SARS-CoV-2 was rare in patients with inactive AOSD. Local and systemic adverse reactions were found to be mild and self-limiting. These safety profiles of inactivated SARS-CoV-2 vaccines in patients with AOSD may assist in eliminating vaccine hesitancy and increase the vaccination rate against SARS-CoV-2.

COVID-19 vaccine affects neither prothrombotic antibody profile nor thrombosis in primary anti-phospholipid syndrome: a prospective study.

OBJECTIVE: To explore whether inactivated coronavirus disease 2019 vaccine influences the profile of prothrombotic autoantibodies and induces thrombotic events in primary APS patients. METHODS: We enrolled 39 primary APS patients who received two doses of inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine (BBIBPCorV, Sinopharm, Beijing, China) voluntarily in this prospective cohort. Prothrombotic autoantibodies were determined before vaccination and 4 weeks after the second dose of vaccination. Thrombotic disorders were evaluated via hospital site visits and assessments. RESULTS: There was no significant difference in the presence of all 11 autoantibodies detected before and 4 weeks after vaccination: for aCL, IgG (14 vs 16, P = 0.64), IgM (13 vs 19, P = 0.34), IgA (2 vs 3, P = 0.64); anti-ß2GP1, IgG (12 vs 12, P = 1.00), IgM (5 vs 8, P = 0.36), IgA (4 vs 3, P = 0.69); anti-PS/PT IgG (13 vs 16, P = 0.48), IgM (17 vs 22, P = 0.26); LAC (22 vs 28, P = 0.16); aPF4-heparin (0 vs 0, P = 1.00) and ANA (23 vs 26, P = 0.48). Notably, the distribution of the aPL profile in the pre- and post-vaccination cohorts was not affected by SARS-CoV-2 vaccination: for patients with a low-risk aPL profile (11 vs 10, P = 0.799) and patients with a high-risk aPL profile (28 vs 29, P = 0.799), respectively. Furthermore, no case exhibited symptoms of the thrombotic disorder during a minimum follow-up period of 12 weeks. There was no adjustment to the ongoing treatment regimens following SARS-CoV-2 vaccination. CONCLUSION: Inactivated SARS-CoV-2 vaccine does not influence the profile of anti-phospholipid antibodies and anti-PF4-heparin antibodies nor induces thrombotic events in primary APS patients.

The landscape of innate and adaptive immune cell subsets in patients with adult-onset Still's disease.

OBJECTIVE: Adult-onset Still's disease (AOSD) is a systemic autoinflammatory disorder. The understanding of the changes in adaptive immune cells and the crosstalk between innate and adaptive immune systems in AOSD is limited. This study aimed to examine the peripheral immune cell composition and inflammatory protein levels in AOSD patients. METHODS: Twenty-nine active AOSD patients were enrolled. Flow cytometry was used to analyze the cell populations in peripheral blood. Antibody chips were utilized to detect the protein expression profile in serum. RESULTS: In active AOSD patients, there was an increase in the percentage of classical and non-classical monocytes among peripheral blood mononuclear cells. The proportion of natural killer (NK) cells decreased, with an increase in CD56dim NK1 cells and a decrease in CD56bright NK2 cells compared with healthy controls (HC). The percentage of naïve central memory T cells was decreased, while the percentage of effector and effector memory T cells was increased among adaptive lymphocytes. The proportion of naïve B and memory B cells was decreased, while plasma cells were increased in AOSD patients, indicating activation of the adaptive immune system. Additionally, the serum levels of 40 proteins were elevated in AOSD patients, primarily involved in cytokine-cytokine receptor interaction, inflammatory response, and regulation of MAPK cascade. CONCLUSION: Our findings showed the activation of the innate and adaptive immune system in AOSD. The protein-protein interaction analysis suggested potential communication between innate and adaptive cell subsets. These findings provide new insights into the pathogenesis of the disease and the development of targeted therapies.

Enhanced type I interferon signature induces neutrophil extracellular traps enriched in mitochondrial DNA in adult-onset Still's disease.

Adult-onset Still's disease (AOSD) is a rare but clinically well-known auto-inflammatory disorder. Cytokine storm, the hallmark of AOSD, is mediated by neutrophil hyperactivation and enhanced neutrophil extracellular trap (NET) formation. Type I interferons (IFNs), having a primary role in the initiation of proinflammation responses, can induce subsequent inflammatory cytokine production. However, the role of type I IFNs in AOSD is unclear. Indeed, high levels of IFN-α and IFN-ß expression are presented by AOSD patients. In this investigation, hierarchical unsupervised clustering was performed on IFN-α and IFN-ß data to identify a cluster of AOSD patients who had a serious condition. Neutrophils from treatment-naïve active AOSD patients showed very strong enrichment in their IFN-α response, as shown by RNA-seq and confirmed by the IFN score. Whether IFN-α stimulates NET formation was also tested. IFN-α had the ability to form NETs that contained oxidized mitochondrial DNA (ox-mtDNA). Moreover, the JAK inhibitor could be used to dampen type I IFN-induced NET formation and eventually control ox-mtDNA release. Our results demonstrated the important roles of type I IFNs in the pathogenesis of AOSD through their promotion of NET formation, as characterized by the enhanced level of ox-mtDNA. The findings open up new avenues of research into therapeutic approaches for AOSD.

The high prevalence of abnormal magnetic resonance imaging findings in non-neuropsychiatric patients with persistently positive anti-phospholipid antibodies.

OBJECTIVES: Thrombosis occurring in the central nervous system is common in APS patients, leading to neuropsychiatric symptoms. We investigated the prevalence of silent brain abnormalities on MRI in primary APS (PAPS) patients and aPL carriers and assessed the association between the vascular risk factors, aPL profile, clinical manifestations and MRI abnormalities. METHODS: We consecutively included 44 PAPS patients, 24 aPL carriers and 23 healthy controls with comparable age and gender in a single-centre, observational, cross-sectional study. None of the patients had a history of stroke, transient ischaemic attack, migraine, dementia, epilepsy or bipolar disorders. On cerebral MRI, we assessed the imaging features and location of abnormality. Multivariate analysis was performed to identify the risk factors contributing to the MRI abnormalities. RESULTS: A total of 38 (55.88%) patients had abnormal MRI findings, while only one healthy control showed some abnormalities. Lacunes were the most frequent MRI abnormality in the aPL-positive group [31/68 (45.59%)], which were followed by white matter hyperintensities [20/68 (29.41%)]. In the study population, age [odds ratio (OR) 1.086, P = 0.016] and LA positivity (OR 5.191, P = 0.002) were independent associated factors with brain MRI abnormalities. When analysed in only the aPL-positive group, age (OR 1.116, P = 0.007), female gender (OR 7.519, P = 0.025) and thrombocytopenia (OR 8.336, P = 0.047) were the significant independent risk factors with abnormal MRI. CONCLUSIONS: PAPS patients and aPL carriers showed a high prevalence of brain MRI abnormalities, indicating an increased cerebrovascular risk, which emphasized attention to silent cerebral lesions in persistently aPL-positive patients.

Plasma exchange therapy in refractory inflammatory myopathy with anti-signal recognition particle antibody: a case series.

OBJECTIVES: To explore the efficacy of plasma exchange (PE) therapy in refractory idiopathic inflammatory myopathy (IIM) patients with positive anti-signal recognition particle (SRP) antibody. METHODS: Nine refractory IIM patients with positive anti-SRP antibody were enrolled, who received PE therapy at Ruijin Hospital from October 2017 to December 2020. The clinical manifestations, laboratory tests, chest CT and lower extremity MRI images before and after PE therapy were compared. The treatment response was evaluated by the 2016 ACR/EULAR myositis response criteria. RESULTS: A total of 88.9% (8/9) of subjects had achieved improvement by 3 weeks after PE therapy, with 55.6% (5/9) minimal improvement and 33.3% (3/9) moderate improvement. There were statistically significant improvements between baseline and after PE therapy at 3 weeks on the core set measures: physician global activity, patient global activity, HAQ, manual muscle testing (MMT), extramuscular disease activity, and muscle enzymes activity including creatine kinase (CK), lactate dehydrogenase (LDH), aspartate transaminase (AST), except for alanine transaminase (ALT). Moreover, the chest CT showed regression of ground glass opacities and irregular linear opacities after PE therapy in four patients with interstitial lung disease. The MRI images of lower extremity in four patients showed reduction of muscle oedema after the therapy. CONCLUSION: PE therapy is effective for refractory IIM patients with positive anti-SRP antibody. It should be considered as an alternative treatment for those patients who are resistant to the combined therapy of glucocorticoids and immunosuppressive agents.

Characteristics of purified anti-ß2GPI IgG N-glycosylation associate with thrombotic, obstetric and catastrophic antiphospholipid syndrome.

OBJECTIVE: Anti-ß-2 glycoprotein I (anti-ß2GPI) antibodies, defined as primary pathogenic antibody in antiphospholipid syndrome (APS). It has been reported that IgG Fc N-glycosylation affects IgG effector, we aim to investigate the association of Fc glycosylation profiles of purified anti-ß2GP1 IgG with clinical features of APS. METHODS: We purify anti-ß2GPI IgG and total IgG from 82 APS patients including nine catastrophic antiphospholipid syndrome (CAPS) patients, as well as total IgG from 103 healthy controls to quantitatively analyse all detectable Fc N-glycanforms of all IgG subclasses with Multiple Reaction Monitoring (MRM) method based on UPLC-ESI-QqQ mass spectrometry. RESULTS: Both purified anti-ß2GPI IgG and APS total IgG showed altered N-glycan profiles when compared with healthy control (HC) IgG. Anti-ß2GPI IgG presented with lower galactosylation, increased bisection and core fucosylation compared with APS total IgG and HC IgG. We found higher galactosylation of aß2GPI IgG2 in thrombotic APS compared with the obstetric APS, and lower galactosylation of aß2GPI IgG2 associated with late pregnancy morbidity. Moreover, low galactosylation of all anti-ß2GPI IgG subclasses, increased bisection and core fucosylation of anti-ß2GPI IgG1/2 were strongly associated with CAPS and triple positivity of antiphospholipid antibodies (aPLs). CONCLUSION: We comprehensively characterize the N-Glycans landscape of both anti-ß2GP1 and total IgG in APS. Altered N-glycan profiles of anti-ß2GPI IgG enables enabled the antibodies with proinflammatory properties. Furthermore, we associated levels of IgG Fc-glycosylation with clinical features antiphospholipid syndrome. These findings could increase our understanding of anti-ß2GPI antibody mediated mechanisms in APS and be used to develop diagnostics and new target treatments.

Serum VEGF-C as an evaluation marker of disease activity in adult-onset Still's disease.

In view of the possible involvement of vascular endothelial growth factor-C (VEGF-C) in pathogenesis of adult-onset Still's disease (AOSD) based on our previous genome-wide association study (GWAS) results, the primary objective of this study, therefore, was to investigate the correlations between the content of VEGF-C in serum and clinical and biochemical markers of AOSD. Blood samples were collected from 80 patients with AOSD, 26 with rheumatoid arthritis (RA), 30 with systemic lupus erythematosus (SLE) and 31 healthy control subjects. The serum VEGF-C levels were determined using an enzyme-linked immunosorbent assay (ELISA). Statistical analysis and comparisons were conducted. A significantly higher serum VEGF-C level was observed in patients with AOSD than in HC. Serum VEGF-C levels had high AUC value of 0.8145 for distinguishing AOSD group from healthy group with sensitivity of 0.7097 and specificity of 0.8250. It also showed good diagnostic value to differentiate AOSD from other autoinflammatory diseases with sensitivity of 0.7500 and specificity of 0.5500. AOSD patients with fever, arthralgia, skin rash, sore throat, lymphadenopathy, splenomegaly hepatomegaly and pleuritis, had a higher level than those who did not have these symptoms (p = 0.0012, p = 0.0092, p = 0.0056, p = 0.0123, p = 0.0068, p = 0.0030, p = 0.0020, and p = 0.0018, respectively). The serum VEGF-C levels were also positively correlated with laboratory features and several cytokines related to AOSD disease activity. In conclusion, our study unveiled a close association between serum VEGF-C levels and AOSD including disease activity and clinical hematological manifestations, suggesting the potential utility of VEGF-C as a candidate biomarker to assess disease activity in AOSD.

The amino acid variants in HLA II molecules explain the major association with adult-onset Still's disease in the Han Chinese population.

Adult-onset Still's disease (AOSD) is a rare autoinflammatory disease with systemic involvement, and its pathophysiology remains unclear. Genome-wide association studies (GWAS) in the Chinese population have revealed an association between AOSD and the major histocompatibility complex (MHC) locus; however, causal variants in the MHC remain undetermined. In the present study, we identified independent amino-acid polymorphisms in human leukocyte antigen (HLA) molecules that are associated with Han Chinese patients with AOSD by fine-mapping the MHC locus. Through conditional analyses, we identified position 34 in HLA-DQα1 (p = 1.44 × 10-14) and Asn in HLA-DRß1 position 37 (p = 5.12 × 10-11) as the major determinants for AOSD. Moreover, we identified the associations for three main HLA class II alleles: HLA-DQB1*06:02 (OR = 2.70, p = 3.02 × 10-14), HLA-DRB1*15:01 (OR = 2.44, p = 3.66 × 10-13), and HLA-DQA1*01:02 (OR = 1.97, p = 1.09 × 10-9). This study reveals the relationship between functional variations in the class II HLA region and AOSD, implicating the MHC locus in the pathogenesis of AOSD.

Current and emerging biological therapy in adult-onset Still's disease.

Adult-onset Still's disease (AOSD) is a rare, but characteristic non-familial, multi-genic systemic auto-inflammatory disorder, characterized by high spiking fever, salmon-like evanescent skin rash, polyarthritis, sore throat, hyperferritinemia and leucocytosis. The hallmark of AOSD is a cytokine storm triggered by dysregulation of inflammation. Nowadays, with advances in anti-cytokine biologic agents, the treatment of AOSD is no longer limited to NSAIDs, glucocorticoids or conventional synthetic DMARDs. In this review, we focussed on the roles of these cytokines in the pathogenesis of AOSD and summarized the current and emerging biological therapy.

Characteristics and risk factors of relapses in patients with adult-onset Still's disease: a long-term cohort study.

OBJECTIVES: To describe the detailed characteristics and explore the potential risk factors of relapses in patients with adult-onset Still's disease (AOSD). METHODS: We enrolled patients with AOSD admitted to the Department of Rheumatology and Immunology, Ruijin Hospital from August 2016 to September 2019. Kaplan-Meier curves and the log rank test were used to estimate the cumulative relapse probability and persistent remission rate before the first occurrence of relapse. The multivariate Cox proportional hazard method was utilized to identify risk factors associated with relapses of AOSD. RESULTS: A total of 122 patients with AOSD were enrolled with a median follow-up of 12.6 months. Among them, 26 (21.3%) patients had at least one relapse. The cumulative relapse rates of AOSD patients were 14.42%, 21.79%, 24.81% and 28.57% at 6, 12, 18 and 36 months, respectively. According to the multivariate analysis, intensive treatment (odds ratio: 6.848; 95% CI: 2.441, 19.211) and macrophage activation syndrome (odds ratio: 4.020, 95% CI: 1.564, 10.322) were associated with increased risk of relapse. CONCLUSION: Our study indicated that relapses occurred in at least one-fifth of patients with AOSD, and patients with high disease severity at initial attack may have an increased risk of relapse, which needs more intensive therapy and close follow-up.

Neutrophil-derived lipocalin-2 in adult-onset Still's disease: a novel biomarker of disease activity and liver damage.

OBJECTIVE: Liver damage is a common manifestation and can be life-threatening in adult-onset Still's disease (AOSD), an autoinflammatory disease. The hallmark of AOSD is activation of neutrophils, whose infiltration in liver is suspected to promote tissue injury. Here we aimed to identify a candidate biomarker and to validate its association with liver damage in AOSD. METHODS: Transcriptome analysis of neutrophils from treatment-naïve active AOSD patients and healthy donors was performed. Lipocalin-2 (LCN2) expression was assessed in neutrophils, plasma and liver biopsies of AOSD. The correlations of LCN2 with different variables and its ability to identify liver damage from AOSD patients were analysed. RESULTS: LCN2, a novel biomarker in hepatic inflammation, was found to be upregulated in AOSD neutrophils by RNA sequencing and confirmed at the mRNA and protein levels. Plasma levels of LCN2 were significantly higher in AOSD patients than healthy controls, RA and SLE patients. Plasma LCN2 levels were closely correlated with inflammatory markers, systemic score, HScore and cytokines. Moreover, LCN2 levels were increased in active AOSD with liver involvement and independently associated with liver dysfunction. Enhanced expression of LCN2 was detected in liver biopsies from three patients with ongoing liver injury. Furthermore, the area under the curve value of LCN2 for identifying AOSD with liver injury from other liver diseases was 0.9694. CONCLUSION: Our results reveal that neutrophils-derived LCN2 is higher in plasma and liver tissue in AOSD patients than in healthy controls, and it could serve as a potent biomarker for identifying AOSD with systemic inflammation, especially liver damage caused by hyperinflammation.

Serum sTREM-1 in adult-onset Still's disease: a novel biomarker of disease activity and a potential predictor of the chronic course.

OBJECTIVES: Triggering receptor expressed on myeloid cells-1 (TREM-1) is an amplifier of inflammatory signals. Recently, a soluble form of TREM-1 (sTREM-1) was described. This study aimed to investigate the role of serum sTREM-1 in patients with adult-onset Still's disease (AOSD). METHODS: Serum sTREM-1 levels were detected in 108 AOSD patients, 88 RA patients and 112 healthy controls (HC). The correlations of sTREM-1 with disease activity, clinical characteristics and laboratory parameters in AOSD patients were analysed by the Spearman correlation test. Risk factors for the chronic course of AOSD were evaluated by multivariate logistic regression analysis. RESULTS: AOSD patients had significantly higher serum sTREM-1 levels than RA patients and HC, and serum sTREM-1 levels were correlated with the systemic score, ferritin, leucocyte count, CRP, IL-1ß and IL-6. The elevation in the initial sTREM-1 level by itself could discriminate patients developing the chronic course from patients developing the nonchronic course. Moreover, an elevated sTREM-1 level (> 526.4475 pg/ml) was an independent risk factor for the chronic course in active AOSD patients. Furthermore, interfering with TREM-1 engagement led to reductions in the secretion of pro-inflammatory cytokines, such as IL-1ß, IL-6 and TNF-α, in neutrophils and monocytes from active AOSD patients. CONCLUSION: Serum sTREM-1 levels are correlated with disease activity, and an elevation in the initial serum sTREM-1 level is a potential predictor of the chronic course in AOSD patients, which currently provides the best predictive model for identifying patients prone to developing the chronic course of AOSD.

Clinical features and current treatments of adult-onset Still's disease: a multicentre survey of 517 patients in China.

OBJECTIVES: As a rare systemic autoinflammatory disease, adult-onset Still's disease (AOSD) has heterogeneous clinical manifestations, response to treatment and outcome. This study tried to assess the clinical characteristics, laboratory tests, and treatments of Chinese AOSD patients, and make a retrospective analysis. METHODS: We collected from 7 hospitals in China a total of 517 Chinese patients with AOSD who satisfied the Yamaguchi criteria. We retrospectively evaluated their clinical features, laboratory tests, treatments and compared them with published data from different studies. All the data in this study were from medical records and further statistic analyses. RESULTS: We evaluated a total of 517 AOSD patients, 72% female, average age of onset was 37.7; spiking fever, rash and arthralgia occurred in 472 (91.3%), 413 (79.9%), 378 (73.1%) cases, respectively. There were 439/513 (85.6%) cases with leukocytosis and 456/476 (95.8%) cases with raised serum ferritin. The highest frequently used medications and regimens for remission were glucocorticoids (498/517, 96.3%), methotrexate (273/517, 52.8%) and hydroxychloroquine (174/517, 33.7%). 84.4%. 357/423 of AOSD cases were able to achieve initial remission with different regimens, mostly including glucocorticoids, methotrexate or hydroxychloroquine. 47.2% of them (244/517) received 30