Performance of the 2022 ACR/EULAR Classification Criteria in Comparison With the European Medicines Agency Algorithm in Antineutrophil Cytoplasmic Antibody-Associated Vasculitis.

OBJECTIVE: This study aimed to compare the 2022 American College of Rheumatology (ACR)/European Alliance of Associations for Rheumatology (EULAR) classification criteria with the European Medicines Agency (EMA) algorithm for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). METHODS: All consecutive, newly diagnosed patients with AAV according to the 2012 Chapel Hill Consensus Conference who visited Keio University Hospital between March 2012 and May 2022 were retrospectively reviewed. Patients were reclassified according to the EMA algorithm and the 2022 ACR/EULAR criteria, and their clinical characteristics were statistically analyzed. RESULTS: A total of 114 patients with AAV were included in the analyses. Using the EMA algorithm as a reference, reclassification of the patients revealed sensitivity and specificity of the 2022 ACR/EULAR criteria of 100% and 96% for eosinophilic granulomatosis with polyangiitis, 40% and 97% for granulomatosis with polyangiitis (GPA), and 90% and 49% for microscopic polyangiitis (MPA), respectively. Approximately half of patients classified as EMA-GPA or EMA-unclassifiable were reclassified as 2022-MPA; these patients were older, were more disposed to be positive for myeloperoxidase (MPO)-ANCA, and had interstitial lung disease (ILD) more frequently than patients with 2022-GPA or non-2022-MPA. Further, some patients positive for MPO-ANCA with biopsy-proven granulomatous inflammation were also reclassified from EMA-GPA to 2022-MPA. Over the mean observation period of 4.0 years, 16 patients died. Overall survival for each classification group differed significantly from the 2022 ACR/EULAR criteria (P = 0.02), but not with the EMA algorithm (P = 0.21). CONCLUSION: Among the patients classified as EMA-GPA or EMA-unclassifiable, older patients with MPO-ANCA and ILD tended to be reclassified as 2022-MPA. The 2022 ACR/EULAR criteria were more useful in prognostic prediction than the EMA algorithm.

Tense blisters and hemorrhagic bullae as the first manifestation of eosinophilic granulomatosis with polyangiitis.

Eosinophilic granulomatosis with polyangiitis (EGPA) poses a significant diagnostic challenge due to its varied clinical presentation. Here, we present a case of a 59-year-old female with a history of asthma and sinusitis, who manifested with an extremely rare presentation of drastic tense blisters and hemorrhagic bullae alongside purpuric lesions and peripheral neuropathy. Examinations revealed eosinophilia, positive anti-neutrophil cytoplasmic antibody, and characteristic pathological findings with small vessel vasculitis in the purpura. Treatment with glucocorticoids and cyclophosphamide led to rapid improvement in peripheral eosinophilia, skin manifestations and motor neuron deficits. Although rare, our case underscores that bullous skin lesions should be recognized as a potential cutaneous hallmark of EGPA to aid timely diagnosis, since prompt treatment initiation is crucial given the potential irreversible organ damage and poor prognosis of EGPA.

Human T follicular helper cells and their impact on IgE and IgG4 production across allergy, malignancy, and IgG4-related disease.

Human T follicular helper (Tfh) cells play a crucial role in orchestrating B cell differentiation, maturation, and immunoglobulin class switching. Recent studies have underscored the presence of Bcl-6 + Tfh cells not only in secondary lymphoid organs but also within tertiary lymphoid structures at inflammatory sites, emphasizing their pivotal role in disease pathogenesis. Furthermore, Tfh cells have been found to transit between lesion sites, lymph nodes, and peripheral blood, as revealed by T cell receptor repertoire analysis. Among Tfh subsets, Tfh2 cells have emerged as central orchestrators in driving the production of IgE and IgG4 from B cells. Their critical role in diseases such as allergy, malignancy, and IgG4-related disease highlights their profound impact on balancing inflammation and immune tolerance. Our current review provides the molecular characteristics of human Tfh cells, the differentiation pathways of Tfh subsets, mechanisms by which Tfh subsets induce IgE and IgG4 production, and their clinical implications in allergy, malignancy, and IgG4-related disease.

Risk factors for adverse drug reactions to sulfamethoxazole-trimethoprim prophylaxis in patients with rheumatic and musculoskeletal diseases.

OBJECTIVES: Risk factors for adverse drug reactions (ADRs) associated with prophylactic sulfamethoxazole-trimethoprim (SMX/TMP) in patients with rheumatic and musculoskeletal diseases undergoing immunosuppressive therapy remain unclear, we aimed to identify the risk factors associated with ADRs. METHODS: Consecutive patients with rheumatic and musculoskeletal diseases, who were admitted to Keio University Hospital and received prophylactic administration of SMX/TMP, were included. Data regarding ADRs to SMX/TMP were collected to identify associated risk factors using multivariable analysis. RESULTS: Of 438 patients included in the analysis, 82 (18.7%) experienced ADRs. Patients in the ADRs group were significantly older, had chronic kidney disease, and exhibited lower lymphocyte and platelet counts, lower albumin levels, lower estimated glomerular filtration rates, higher aspartate aminotransferase levels, and higher ferritin levels than those in the non-ADR group. Regarding underlying rheumatic and musculoskeletal diseases, adult-onset Still's disease (ASD) was associated with a significantly higher incidence of ADRs (67%) than other diseases. Multivariable analysis identified the presence of ASD and low lymphocyte counts as independent risk factors for allergic ADRs, and older age and use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers for non-allergic ADRs. CONCLUSIONS: Risk factors for ADRs associated with prophylactic SMX/TMP treatment in patients with rheumatic and musculoskeletal diseases were identified.

Successful maintenance therapy with tocilizumab for severe acute liver failure associated with adult-onset still's disease.

Elevated liver enzymes are commonly observed among adult-onset Still's disease (AOSD), but severe acute liver failure is extremely rare. Although severe acute liver failure associated with AOSD poses a life-threatening condition, the appropriate treatment is unclear. Some case reports have demonstrated the efficacy of high-dose prednisolone (PSL) and cyclosporin A (CyA), although the adverse effects of CyA led certain patients to cease its use. Therefore, an alternative treatment option is crucial, and thus far, there have been no reports of tocilizumab (TCZ) being used for this severe phenotype. Here, we report the first case of successful treatment using TCZ as maintenance therapy for severe ALF associated with AOSD. Following initial treatment with high-dose PSL and CyA, our case was switched to TCZ due to CyA-related side effects including alopecia and tremors. Our case highlights TCZ as a potential option for maintenance therapy of this severe condition.

Longitudinal analysis at pre- and post-flare of T peripheral helper and T follicular helper subsets in patients with systemic lupus erythematosus.

OBJECTIVE: We focused to analyze the time-course changes at pre- and post-flare of T peripheral helper (Tph) cells and circulating T follicular helper (Tfh) cells in the blood of patients with systemic lupus erythematosus (SLE) with lupus low disease activity state (LLDAS) before flare. METHODS: This study included inactive (n = 29) and active (n = 55) patients with SLE. Tph subsets, Tfh subsets, CD11chi B cells, and plasma cells in the blood were determined by flow cytometry. The blood levels of cytokines including interferons (IFNs) were measured by electrochemiluminescence assay or cytokine beads array. RESULTS: Active SLE patients exhibited the increased frequency of Tph1, Tph2, Tfh1, and Tfh2 subsets when compared to inactive patients, but no clear changes in the other subsets. During the treatment with medications, Tph1, Tph2, and Tfh2 subsets were significantly reduced along with disease activity and Tph1 and Tph2 subsets were positively correlated with SLE disease activity index (SLEDAI). The time course analysis of patients at pre- and post-flare revealed that in the patients at LLDAS before flare, Tph subsets and Tfh subsets were relatively low levels. At the flare, Tph cells, particularly Tph1 and Tph2 subsets, were increased and correlated with SLEDAI. Furthermore, the blood levels of IFN-α2a, IFN-γ, and IFN-λ1 were low in the patients with LLDAS before flare but these IFNs, particularly IFN-λ1, were increased along with flare. CONCLUSION: Increased frequency of Tph1 and Tph2 subsets and elevated levels of serum IFN-λ1 are presumably critical for triggering of flare in SLE.

Successful high-dose glucocorticoid therapy for anti-mitochondrial antibody-positive myocarditis arising during tocilizumab and low-dose glucocorticoid therapy for rheumatoid arthritis.

Anti-mitochondrial antibody (AMA)-positive myopathy, a recently identified condition with significant cardiac involvement, poses a serious challenge in treatment consensus due to its extreme rarity. While several studies demonstrate the efficacy of high-dose prednisolone in managing this disease, the current literature lacks substantial evidence regarding the effectiveness of biologic therapy or low-dose prednisolone for remission induction. Here, we present a case of AMA-positive myocarditis that emerged during rheumatoid arthritis treatment with tocilizumab (TCZ) and low-dose prednisolone (PSL). Successfully, intensive immunosuppressive therapy with high-dose PSL proved effective in stabilizing this condition. Our case highlights the necessity of a robust immunosuppressive approach, favoring high-dose PSL over the combination of low-dose PSL and TCZ in this disease.

Cytotoxic Tph subset with low B-cell helper functions and its involvement in systemic lupus erythematosus.

T peripheral helper (Tph) cells are thought to contribute to extra-follicular B cell activation and play a pathogenic role in autoimmune diseases. However, the role of Tph subsets is not fully elucidated. Here, we investigate the immunological functions of Tph subsets and their involvement in systemic lupus erythematosus (SLE). We have defined four Tph subsets (Tph1: CXCR3+CCR6-, Tph2: CXCR3-CCR6-, Tph17: CXCR3-CCR6+, and Tph1-17: CXCR3+CCR6+) and performed RNA sequencing after cell sorting. Tph1 and Tph17 subsets express substantial levels of IL21, indicating B cell helper functions. However, Tph2 and Tph1-17 subsets express low IL21. Interestingly, we have found Tph2 subset express high levels of CX3CR1, GZMB, PRF1, GLNY, S1PR5, TBX21, EOMES, ZNF863, and RUNX3, indicating a feature of CD4+ cytotoxic T lymphocytes. In SLE patients, the frequency of Tph1 and Tph2 subsets are significantly increased and positively correlated with SLE disease activity indexes. Tph1 cells expansion has been observed in patients with cutaneous and musculoskeletal manifestations. On the other hand, Tph2 cell expansion has been found in patients with lupus nephritis in addition to the above manifestations. Our findings imply that Tph1 and Tph2 subsets exert distinct immunological functions and are contributed to the complexity of clinical manifestations in SLE.

A Case of Successful Immunosuppressive Therapy for Interstitial Lung Disease Associated with Sjögren's Syndrome With Double-positive Anti-SS-A and Anti-centromere Antibodies.

Sjögren's syndrome (SS) can present with extraglandular organs, such as interstitial lung disease (ILD). Anti-SS-A antibody is frequently found in SS cases, whereas anti-centromere antibody (ACA) is detected in some SS cases. Notably, the anti-SS-A and ACA double-positive cases exhibited distinct features with a higher prevalence of ILD. However, there have so far been no reports on the treatment of ILD in anti-SS-A and ACA double-positive cases. We herein present a case of ILD with anti-SS-A and ACA double-positive SS that was successfully treated with immunosuppressive therapy. Our case suggests the potential efficacy of immunosuppressive therapy for this poorly understood condition.

Successful Treatment of Rosai-Dorfman Disease with Cutaneous Involvement and Arthritis with Methotrexate and Infliximab.

Rosai-Dorfman disease (RDD) is a rare histiocytic proliferative disorder characterized by lymphadenopathy and extra-nodal manifestations. Some patients with RDD require systemic treatment, but there is no consensus on the treatment strategy owing to its extreme rarity. Overexpression of tumor necrosis factor α (TNF-α) has been reported in lesions of patients with RDD and is thought to be involved in its pathogenesis. We herein report the first case of RDD with cutaneous involvement and arthritis that was successfully treated with methotrexate and infliximab. This case highlights the potential efficacy of anti-TNF-α therapy for RDD, offering a novel treatment option for this rare condition.

Th17/IL-17A axis is critical for pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc): SSc patients with high levels of serum IL-17A exhibit reduced lung functions and increased prevalence of PAH.

BACKGROUND: It is thought that systemic sclerosis (SSc) might be a T helper 17 (Th17) cell-driven autoimmune disease. Noticeably, pulmonary arterial hypertension (PAH) is a leading cause of death in patients with SSc. Here, we investigated the association between serum Th17-related cytokines and prevalence of PAH in SSc patients. METHODS: This study included 72 SSc patients and 51 healthy controls (HC). We determined clinical manifestations, immunophenotypes including Th subsets in peripheral blood lymphocytes, and the serum levels of interleukin (IL)-17A, IL-17A/F, IL-17B. IL-17C, IL-17D. IL-1ß, IL-6, IL-21, IL-22, and IL-23. RESULTS: The frequency of Th17 cells was significantly increased in SSc patients compared to HC and was positively correlated with the modified Rodnan skin scores. Furthermore, the serum levels of IL-17A, IL-17D, IL-1ß, and IL-6 were significantly increased in SSc patients compared to HC. SSc patients with detected IL-17A showed high levels of IL-17A/F, IL-1ß, IL-6, and IL-22, and high frequency of Th17 cells. Interestingly, these patients exhibited the reduced lung functions and increased prevalence of PAH significantly compared to patients with undetected IL-17A. Similarly, SSc patients with detected IL-17A and high IL-6 (≥1.2 pg/mL) exhibited the decreased lung functions and increased prevalence of PAH compared to patients with undetected IL-17A and low IL-6. CONCLUSION: We found that SSc patients with high levels of serum IL-17A or both IL-17A and IL-6 show reduced lung functions and high prevalence of PAH. Consequently, it is highly probable that Th17/IL-17A axis is critical for the prevalence of PAH in SSc patients.

Does a window of opportunity for rheumatoid arthritis-associated interstitial lung disease exist?

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammatory synovitis, eventually leading to joint destruction. Remarkable advancements in the emergence of molecular targeted therapies and the treatment strategy based on treat-to-target have made it possible for patients to lead their daily lives without disabilities. Specifically, early diagnosis and appropriate treatment without missing a 'window of opportunity' are crucial for improving joint outcomes. On the other hand, interstitial lung disease (ILD) is an extra-articular complication of RA and has an impact on life prognosis. Importantly, it has become evident that achieving remission of arthritis is critical not only for joint outcomes but also to prevent the irreversible progression of pulmonary fibrosis in RA-ILD. Therefore, a 'window of opportunity' may exist not only for joints but also for RA-ILD. However, within RA-ILD, there are cases that progress from an NSIP pattern or airway involvement to a UIP pattern, while there are cases without progression, suggesting that their disease behavior may be diverse. Thus, accumulating evidence is necessary to accurately determine the disease behavior of RA-ILD. This review provides an overview of clinical and radiological features and treatment strategies for RA-ILD, incorporating the latest findings.

Re-emphasising the importance of catheter-based angiography to differentiate polyarteritis nodosa from cutaneous arteritis: Two case reports.

Polyarteritis nodosa (PAN) is a systemic necrotising vasculitis with a poor prognosis, characterised by inflammation and necrosis of medium-sized arteries. PAN patients can present with a wide range of systemic manifestations, whereas cutaneous arteritis (CA) is a restricted manifestation to skin of the disease with a more favourable prognosis. Thus, differentiation between PAN and CA is crucial. Here, we present two cases that were initially diagnosed as CA due to the limited presence of systemic symptoms, but were finally diagnosed as PAN through catheter-based angiography. Although contrast-enhanced computed tomography and computed tomographic angiography are increasingly used to diagnose PAN, neither case had any abnormal findings on these examinations. Our cases therefore underscore that catheter-based angiography is critical for differentiation between PAN and CA, even in cases with limited systemic symptoms.

Significant association of CX3CR1+CD8 T cells with aging and distinct clinical features in Sjögren's syndrome and IgG4-related disease.

OBJECTIVES: Recent studies have implicated cytotoxic CD4 and CD8 T cells in primary Sjögren's syndrome (pSS) and IgG4-related disease (IgG4-RD), but their association with immune aging and organ-specific clinical features remain unclear. CX3CR1 is expressed on cytotoxic CD4 and CD8 T cells. The aim of this study was to determine associations of peripheral CX3CR1+CD4 and CX3CR1+CD8 T cells with aging and clinical features. METHODS: Whole blood samples were freshly obtained from consecutive patients with active, treatment-naïve pSS (n=57), IgG4-RD (n=54), and healthy individuals (n=40) and analysed by flow cytometry for CX3CR1+CD4 and CX3CR1+CD8 proportions. Associations of those T cells with aging and clinical features were determined. RESULTS: CX3CR1+CD4 and CX3CR1+CD8 T cells selectively expressed perforin and granzyme B. Proportions of CX3CR1+CD4 and CX3CR1+CD8 T cells were significantly higher in pSS and IgG4-RD than in healthy individuals. Higher proportions of CX3CR1+CD8 T cells were associated with aging in pSS and IgG4-RD but not in healthy individuals. Sex differences were not associated with proportions of CX3CR1+CD8 T cells. Furthermore, patients with pSS with interstitial lung disease showed higher proportions of CX3CR1+CD8 T cells than those without interstitial lung disease. IgG4-RD patients with retroperitoneal fibrosis and/or aortitis exhibited higher proportions of CX3CR1+CD8 T cells compared with those with Mikulicz's disease. Moreover, proportions of CX3CR1+CD8 T cells were decreased following glucocorticoid treatment in paralleled with clinical improvements in IgG4-RD. CONCLUSIONS: CX3CR1+CD8 T cells might be involved in immune aging and distinct clinical phenotypes of patients with pSS or IgG4-RD.

Sarcopenia in patients with rheumatic musculoskeletal diseases.

AIM: To investigate the impact of high-dose glucocorticoid therapy on sarcopenia in hospitalized patients with rheumatic musculoskeletal diseases (RMDs). METHODS: We included patients with RMDs who were hospitalized between 2020 and 2022 for remission induction treatment and collected information on skeletal mass index (SMI) before high-dose glucocorticoid therapy and 1 month later. We divided the patients into 2 groups according to the progression of sarcopenia, defined as a >10% decrease in SMI, and compared their clinical characteristics. RESULTS: Forty-nine patients were included in this analysis. The mean age was 53.3 years, 73.5% were female, and the mean SMI was 5.3 kg/m2 . Before treatment, 83.7% had already met the definition of sarcopenia, and 57.1% experienced further sarcopenia progression after 1 month of high-dose glucocorticoid treatment. Patients with sarcopenia progression were predominantly male (P = 0.025), had a higher body weight (P = 0.048), and showed a higher SMI than those without sarcopenia at baseline (P = 0.008). Multivariable analysis revealed that body weight increase from 0 to week 1 of high-dose glucocorticoid treatment was associated with sarcopenia progression (odds ratio: 0.22, 95% CI: 0.04-0.61, P = 0.007) with a cut-off of -1.8 kg. During a mean observation period of 30.2 days, the incidence of infection was significantly higher in patients with progressive sarcopenia (P = 0.042). CONCLUSIONS: One-month hospitalization with high-dose glucocorticoid therapy is associated with sarcopenia progression in patients with RMDs. An early decrease in body weight can be used to predict muscle volume loss.

T follicular helper cells and T peripheral helper cells in rheumatic and musculoskeletal diseases.

Recent technological progress has greatly advanced our understanding of human immunology. In particular, the discovery of human T follicular helper (Tfh) and T peripheral helper (Tph) cells has significantly advanced our understanding of human adaptive immune system. Tfh and Tph cells share similar molecular characteristics and both play critical roles in B cell differentiation and maturation. However, they differ in their functional properties, such as chemokine receptor expression and cytokine production. As a result, Tfh cells are mainly involved in B cell differentiation and maturation in germinal centres of secondary lymphoid tissues, while Tph cells are involved in B cell differentiation and tissue damage in peripheral inflammatory lesions. Importantly, the involvement of Tfh and Tph cells in the pathogenesis of rheumatic and musculoskeletal diseases has become clear. In rheumatoid arthritis and systemic lupus erythematosus, Tph cell infiltration is predominant in peripheral inflammatory lesions, whereas Tfh cell infiltration is predominant in the affected lesions of IgG4-related disease. Therefore, the contribution of Tfh and Tph cells to the development of rheumatic and musculoskeletal diseases varies depending on each disease. In this review, we provide an overview of human Tfh and Tph cells and summarise the latest findings on these novel T cell subsets in various rheumatic and musculoskeletal diseases.

Successful treatment of PR3-ANCA-positive interstitial pneumonia with a moderate dose of glucocorticoid and rituximab.

Antineutrophil cytoplasmic antibody (ANCA)-positive interstitial pneumonia (IP) is reported as IP that is ANCA-positive and does not involve organ damage associated with vasculitis other than the lungs. While the combination of glucocorticoid and rituximab is effective in ANCA-associated vasculitis, the treatment strategy for ANCA-positive IP has not been established. Here, we report the first case of successful treatment of proteinase 3 (PR3)-ANCA-positive IP with a moderate dose of glucocorticoid and rituximab. The patient was an 80-year-old male who presented with subacute dry cough and dyspnoea. Blood tests revealed elevated levels of C-reactive protein, Krebs von den Lungen 6 (KL-6), and PR3-ANCA. Chest computed tomography (CT) showed interstitial shadows and infiltrates around honeycomb cysts. 18F-fluorodeoxyglucose (FDG) positron emission tomography CT revealed an uptake of FDG in the IP area. After starting treatment with a moderate dose of prednisolone and rituximab, the patient's clinical symptoms disappeared, C-reactive protein and KL-6 turned to be normal, and infiltrates around the cysts of honeycomb lungs disappeared. Prednisolone was gradually decreased to 2 mg, and no relapse or adverse events were observed during the course of treatment. Our case suggests that early treatment with a moderate dose of glucocorticoid and rituximab is effective for PR3-ANCA-positive IP.