Significance of clinical-immunological patterns and diagnostic yield of biopsies in microscopic polyangiitis and granulomatosis with polyangiitis.

BACKGROUND: Microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA) are the two major antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). OBJECTIVES: To characterize a homogenous AAV cohort and to assess the impact of clinicopathological profiles and ANCA serotypes on clinical presentation and prognosis. Clinical differences in GPA patients according to ANCA serotype and the diagnostic yield for vasculitis of biopsies in different territories were also investigated. RESULTS: This retrospective study (2000-2021) included 152 patients with AAV (77 MPA/75 GPA). MPA patients (96.1% myeloperoxidase [MPO]-ANCA and 2.6% proteinase 3 [PR3]-ANCA) presented more often with weight loss, myalgia, renal involvement, interstitial lung disease (ILD), cutaneous purpura, and peripheral nerve involvement. Patients with GPA (44% PR3-ANCA, 33.3% MPO, and 22.7% negative/atypical ANCA) presented more commonly with ear, nose, and throat and eye/orbital manifestations, more relapses, and higher survival than patients with MPA. GPA was the only independent risk factor for relapse. Poor survival predictors were older age at diagnosis and peripheral nerve involvement. ANCA serotypes differentiated clinical features in a lesser degree than clinical phenotypes. A mean of 1.5 biopsies were performed in 93.4% of patients in different territories. Overall, vasculitis was identified in 80.3% (97.3% in MPA and 61.8% in GPA) of patients. CONCLUSIONS: The identification of GPA presentations associated with MPO-ANCA and awareness of risk factors for relapse and mortality are important to guide proper therapeutic strategies in AAV patients. Biopsies of different affected territories should be pursued in difficult-to-diagnose patients based on their significant diagnostic yield.

Enhanced efficacy of the novel recombinant clone VasSF in a mouse model of antineutrophil cytoplasmic antibody-associated vasculitis.

Based on the efficacy of intravenous immunoglobulin (IVIg) for the treatment of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), we developed a recombinant single-chain-fragment variable clone, VasSF, therapeutic against AAV in a mouse model (SCG/Kj mice). VasSF is thought to bind to vasculitis-associated apolipoprotein A-II (APOA2) as a target molecule. VasSF is a promising new drug against AAV, but difficulties in the yield and purification of VasSF remain unresolved. We produced monomers of new VasSF molecules by modifying the plasmid structure for VasSF expression and simplifying the purification method using high-performance liquid chromatography. We compared the therapeutic effects between 5-day continuous administration of the monomers, as in IVIg treatment, and single shots of 5-day-equivalent doses. We also evaluated the life-prolonging effect of the single-shot treatment. Two-dimensional western blots were used to examine the binding of VasSF to APOA2. Our improved manufacturing method resulted in a 100-fold higher yield of VasSF than in our previous study. Monomerization of VasSF stabilized its efficacy. Single shots of a small amount (1/80 000 of IVIg) produced sufficient therapeutic effects, including decreased glomerular crescent formation, a decreasing trend of serum ANCA against myeloperoxidase (MPO-ANCA), decreases in multiple proinflammatory cytokines, and a trend toward prolonged survival. Two-dimensional western blots confirmed the binding of VasSF to APOA2. The newly produced pure VasSF monomers are stable and therapeutic for AAV with a single low-dose injection, possibly by removing vasculitis-associated APOA2. Thus, the new VasSF described herein is a promising drug against AAV.

EULAR recommendations for the management of ANCA-associated vasculitis: 2022 update.

BACKGROUND: Since the publication of the EULAR recommendations for the management of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in 2016, several randomised clinical trials have been published that have the potential to change clinical care and support the need for an update. METHODS: Using EULAR standardised operating procedures, the EULAR task force undertook a systematic literature review and sought opinion from 20 experts from 16 countries. We modified existing recommendations and created new recommendations. RESULTS: Four overarching principles and 17 recommendations were formulated. We recommend biopsies and ANCA testing to assist in establishing a diagnosis of AAV. For remission induction in life-threatening or organ-threatening AAV, we recommend a combination of high-dose glucocorticoids (GCs) in combination with either rituximab or cyclophosphamide. We recommend tapering of the GC dose to a target of 5 mg prednisolone equivalent/day within 4-5 months. Avacopan may be considered as part of a strategy to reduce exposure to GC in granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA). Plasma exchange may be considered in patients with rapidly progressive glomerulonephritis. For remission maintenance of GPA/MPA, we recommend rituximab. In patients with relapsing or refractory eosinophilic GPA, we recommend the use of mepolizumab. Azathioprine and methotrexate are alternatives to biologics for remission maintenance in AAV. CONCLUSIONS: In the light of recent advancements, these recommendations provide updated guidance on AAV management. As substantial data gaps still exist, informed decision-making between physicians and patients remains of key relevance.

Efficacy and safety of avacopan in patients with ANCA-associated vasculitis receiving rituximab in a randomised trial.

OBJECTIVES: To evaluate the efficacy and safety of avacopan in the subgroup of patients with antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis receiving background induction therapy with rituximab in the phase 3 ADVOCATE trial. METHODS: Key efficacy outcomes were remission at week 26 and sustained remission at week 52. Additional outcomes included the Glucocorticoid Toxicity Index, estimated glomerular filtration rate, urinary albumin to creatinine ratio, health-related quality of life and safety. RESULTS: Of the 330 patients who received study medication, 214 (64.8%) received rituximab (once weekly for 4 weeks), with a mean age of 59.8 years; 163 (76.2%) had renal vasculitis and 125 (58.4%) were newly diagnosed. Remission at week 26 and sustained remission at week 52 were achieved by 83/107 (77.6%) and 76/107 (71.0%) patients in the avacopan group and 81/107 (75.7%) and 60/107 (56.1%) in the prednisone taper group, respectively. The relapse rate, recovery of renal function, speed of reduction in albuminuria and glucocorticoid toxicity favoured the avacopan group. Serious adverse events occurred in 34.6% and 39.3% of patients in the avacopan and prednisone taper groups, respectively. CONCLUSIONS: These data suggest that in patients with ANCA-associated vasculitis receiving rituximab, efficacy of treatment with avacopan compared with a prednisone taper was similar at week 26 and greater at week 52, with a favourable safety profile. In addition, avacopan was associated with improved renal outcomes and lower glucocorticoid toxicity. These results demonstrate the efficacy and safety of avacopan in patients receiving background induction therapy with rituximab. TRIAL REGISTRATION NUMBER: NCT02994927.

Data quality and patient characteristics in European ANCA-associated vasculitis registries: data retrieval by federated querying.

OBJECTIVES: This study aims to describe the data structure and harmonisation process, explore data quality and define characteristics, treatment, and outcomes of patients across six federated antineutrophil cytoplasmic antibody-associated vasculitis (AAV) registries. METHODS: Through creation of the vasculitis-specific Findable, Accessible, Interoperable, Reusable, VASCulitis ontology, we harmonised the registries and enabled semantic interoperability. We assessed data quality across the domains of uniqueness, consistency, completeness and correctness. Aggregated data were retrieved using the semantic query language SPARQL Protocol and Resource Description Framework Query Language (SPARQL) and outcome rates were assessed through random effects meta-analysis. RESULTS: A total of 5282 cases of AAV were identified. Uniqueness and data-type consistency were 100% across all assessed variables. Completeness and correctness varied from 49%-100% to 60%-100%, respectively. There were 2754 (52.1%) cases classified as granulomatosis with polyangiitis (GPA), 1580 (29.9%) as microscopic polyangiitis and 937 (17.7%) as eosinophilic GPA. The pattern of organ involvement included: lung in 3281 (65.1%), ear-nose-throat in 2860 (56.7%) and kidney in 2534 (50.2%). Intravenous cyclophosphamide was used as remission induction therapy in 982 (50.7%), rituximab in 505 (17.7%) and pulsed intravenous glucocorticoid use was highly variable (11%-91%). Overall mortality and incidence rates of end-stage kidney disease were 28.8 (95% CI 19.7 to 42.2) and 24.8 (95% CI 19.7 to 31.1) per 1000 patient-years, respectively. CONCLUSIONS: In the largest reported AAV cohort-study, we federated patient registries using semantic web technologies and highlighted concerns about data quality. The comparison of patient characteristics, treatment and outcomes was hampered by heterogeneous recruitment settings.

CD19-targeting CAR T cells protect from ANCA-induced acute kidney injury.

OBJECTIVES: Anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitides (AAV) are life-threatening systemic autoimmune diseases manifesting in the kidneys as necrotizing crescentic glomerulonephritis (NCGN). ANCA antigens are myeloperoxidase (MPO) or proteinase 3. Current treatments include steroids, cytotoxic drugs and B cell-depleting antibodies. The use of chimeric antigen receptor (CAR) T cells in autoimmune diseases is a promising new therapeutic approach. We tested the hypothesis that CAR T cells targeting CD19 deplete B cells, including MPO-ANCA-producing B cells, thereby protecting from ANCA-induced NCGN. METHODS: We tested this hypothesis in a preclinical MPO-AAV mouse model. NCGN was established by immunisation of MPO-/- mice with murine MPO, followed by irradiation and transplantation with haematopoietic cells from wild-type mice alone or together with either CD19-targeting CAR T cells or control CAR T cells. RESULTS: CD19 CAR T cells efficiently migrated to and persisted in bone marrow, spleen, peripheral blood and kidneys for up to 8 weeks. CD19 CAR T cells, but not control CAR T cells, depleted B cells and plasmablasts, enhanced the MPO-ANCA decline, and most importantly protected from NCGN. CONCLUSION: Our proof-of-principle study may encourage further exploration of CAR T cells as a treatment for ANCA-vasculitis patients with the goal of drug-free remission.

Isolation and characterisation of PR3-specific B cells and their immunoglobulin sequences.

BACKGROUND: PR3 autoantibodies are essential to the diagnosis and monitoring of granulomatosus with polyangiitis, but to date no PR3 autoantibody sequences have been published. OBJECTIVES: To identify and characterise PR3-specific B cells from the peripheral blood of patients with PR3 autoantibodies. METHODS: Peripheral blood mononuclear cells from seven patients with PR3 autoantibodies were stained with PR3. B cells that bound PR3 underwent single cell sorting, transcriptome sequencing, and their immunoglobulin sequences expressed as antibodies and tested for PR3-specificity by ELISA. RESULTS: We identified 19 PR3-specific B cells from only one PR3-seropositive patient at a low frequency (0.0075 % of B cells) in the peripheral blood. These were polyclonal, IgG+ and enriched for IgG4, lambda pairing, IGHJ6 gene usage, CDRH3 length, IGHE and CD71 expression. They demonstrated relatively low levels of somatic hypermutation and variably reduced PR3 binding when reverted to germline. CONCLUSIONS: Identifying PR3-specific B cells in the peripheral blood is possible but challenging and those we did identify exhibited features suggesting that PR3-self reactivity may occur early in B-cell development.

Epidemiology of ANCA vasculitis in Northern Spain.

OBJECTIVES: The incidence of anti-neutrophil cytoplasmic antibodies (ANCA) associated vasculitis (AAV) shows disparate results due to variable classification criteria and heterogeneous-population series. We aimed to estimate the incidence of AAV in a well-defined population with standardized classification criteria. METHODS: Population-based study of AAV patients diagnosed from January 2000 to December 2023 in Cantabria, Northern Spain. Patients were classified according to ACR/EULAR 2022 into granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), or unclassified vasculitis if the criteria were not met. Eosinophilic granulomatosis with polyangiitis (EGPA) patients were not included. The annual incidence rates were estimated by cases over 1,000 000 (106) (95% CI) including overall AVV, type of AAV, sex, and year of diagnosis. A literature review was also performed. RESULTS: We included 152 (80/72 men; mean age; 70.6 ± 13.18 years) patients. They were classified as MPA (67; 44%), GPA (64; 42.2%), and unclassified vasculitis (21; 13.8%). Annual incidence was 13.4 (10-16.8)/106 [male 14.5 (10.5-18.5); female 12.1 (8.7-15.6)]. The Annual incidence of MPA was 5.9 (4-7.8)/106 and GPA 5.6 (3.9-7.3)/106. The mean Annual incidence increased from 6.1 (4.5-7.7)/106-16.5 (5.6-27.4)/106 in the last three years, particularly, in GPA from 2.3 (0.3-4.9)/106-8.2 (2-14.5)/106. The prevalence of AAV was 184.7 (181-188)/106. CONCLUSION: During a 20-year period we found that the incidence of AAV (GPA and MPA) in Northern Spain is higher than Southern Spain, but lower than Northern European countries. An increase in the incidence was observed in the last years.

Effectiveness of intravenous methylprednisolone pulse in patients with severe microscopic polyangiitis and granulomatosis with polyangiitis.

OBJECTIVES: To evaluate the effectiveness and safety of two different intravenous methylprednisolone (IVMP) pulse doses in patients with severe microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA). METHODS: We emulated a target trial using observational data from the nationwide registry in Japan. Patients with severe glomerulonephritis or diffuse alveolar haemorrhage were selected and pseudo-randomised into three groups using propensity score-based overlap weighting as follows: non-IVMP, IVMP 0.5 g/day, and IVMP 1.0 g/day. The primary outcome was all-cause death, and the secondary outcomes were composite all-cause death and kidney failure, severe relapse, and serious infection from 2 to 48 weeks after treatment initiation. To estimate the treatment effects, the Cox proportional hazard model and Fine-Gray subdistribution hazard model were used. RESULTS: In this emulated target trial, of 201 eligible patients (MPA, 175; GPA, 26), 6 (2.8%) died, 4 (2.0%) had kidney failure, 11 (5.3%) had severe relapse, and 40 (19.8%) had severe infections. Hazard ratios (HR) for IVMP 0.5 g/day and IVMP 1.0 g/day pulse groups compared with non-IVMP pulse were as follows: all-cause death = 0.46 (95% confidence interval [95%CI]: 0.07-2.81) and 0.07 (95%CI: 0.01-0.41); all-cause death/kidney failure = 1.18 (95%CI: 0.26-5.31) and 0.59 (95%CI: 0.08-4.52); subdistribution HRs for severe relapse = 1.26 (95%CI: 0.12-13.70) and 3.36 (95%CI: 0.49-23.29); and serious infection = 1.88 (95%CI: 0.76-4.65) and 0.94 (95%CI: 0.28-3.13). CONCLUSIONS: IVMP 1.0 g/day pulse may improve 48-week mortality in patients with severe MPA/GPA.

Trimethoprim sulfamethoxazole prophylaxis and serious infections in granulomatosis with polyangiitis treated with rituximab.

OBJECTIVE: To assess the association of trimethoprim sulfamethoxazole (TMP-SMX) prophylaxis with serious infections in rituximab-treated patients with granulomatosis with polyangiitis (GPA). METHODS: This retrospective cohort study included adults with GPA (2011-2020) within the United States Merative™ Marketscan® Research Databases with ≥6 months enrolment prior to first (index) rituximab treatment. We defined TMP-SMX prophylaxis as a ≥28-day prescription dispensed after or overlapping the index date. Serious infection was a hospital primary diagnosis for infection (excluding viral or mycobacterial codes). Secondary outcomes were outpatient infection, PJP, and adverse events potentially attributable to TMP-SMX. Cox proportional hazards regression assessed the association of time-varying TMP-SMX with outcomes of interest, adjusting for potential confounders. Individuals were followed until the outcome of interest, end of database enrolment, or Dec 31, 2020. RESULTS: Among 919 rituximab-treated individuals (53% female), mean age was 52.1 years (SD 16) and 281 (31%) were dispensed TMP-SMX within 30 days of index date. Over a median of 496 (IQR 138, 979) days, 130 serious infections occurred among 104 individuals (incidence 6.1 [95% CI 5.0-7.4] per 100 person-years). Time-varying TMP-SMX was negatively associated with serious infection (adjusted HR 0.5; 95% CI 0.3-0.9). The aHR for outpatient infections was 0.8 (95% CI 0.6-1.1). The estimate for PJP was imprecise (13 events, unadjusted HR 0.2; 95% CI 0.03-1.8). TMP-SMX was potentially associated with adverse events (aHR 1.3; 95% CI 0.9-1.9). CONCLUSIONS: TMP-SMX prophylaxis was associated with reduced serious infections in rituximab-treated GPA, but may increase adverse events, warranting further study of optimal prophylaxis strategies.

Granulomatosis With Polyangiitis With And Without Antineutrophil Cytoplasmic Antibodies: A Case-Control Study.

BACKGROUND: ANCA-negative GPA remains a diagnosis of exclusion. Clinical differences between patients with ANCA-negative vs ANCA-positive GPA have not been analyzed in sizable case-control studies, and the effects of ANCA-seroconversion from negative to positive are not well documented. METHODS: A single-center, sex, and age matched case-control study evaluated ANCA-negative vs ANCA-positive GPA from January 1, 1996, to December 31, 2015. Patients who experienced seroconversion were the subject of a case crossover study. Clinical data and outcomes were retrieved from electronic medical records. RESULTS: ANCA-negative GPA was identified in 110 patients; 65% were female; median age was 55 (IQR 39-65) years at time of diagnosis. Disease severity was milder in ANCA-negative GPA (BVAS/WG = 2 vs 6, p< 0.001). Mucous membranous/eye manifestations were more frequent in ANCA-negative GPA. General symptoms, pulmonary, and renal involvement were more frequent in ANCA-positive GPA. Patients with ANCA-positive GPA relapsed more over 60 months (21.8% vs.9.1%, p= 0.009) compared with ANCA-negative GPA and had shorter time to event (p= 0.043). Patients with general manifestations, BMI > 30kg/m2 and necrotizing granulomatous inflammation were more likely to relapse. The 16 patients who seroconverted into ANCA-positive during follow-up had higher mean BVAS/WG at time of diagnosis (p< 0.001) and increased incidence of relapses (p= 0.004) after seroconversion. Necrotizing granulomatous inflammation on biopsy in ANCA-negative GPA patients was identified as a risk factor for subsequent seroconversion to ANCA-positivity. CONCLUSION: Patients with ANCA-negative GPA have milder disease and a lower frequency of relapse than those with ANCA-positive GPA. ANCA appearance portended higher disease severity and an increased frequency of relapses.

Kv1.3 blockade by ShK186 modulates CD4+ effector memory T-cell activity of patients with granulomatosis with polyangiitis.

OBJECTIVES: Granulomatosis with polyangiitis (GPA) is a chronic relapsing systemic autoimmune vasculitis. Current treatment of GPA is unsatisfactory, as it relies on strong immunosuppressive regimens, with either CYC or rituximab, which reduce the immunogenicity of several vaccines and are risk factors for a severe form of COVID-19. This emphasizes the need to identify new drug targets and to develop treatment strategies with less harmful side effects. Since CD4+ effector memory T cells (TEM) play a key role in the pathogenesis of GPA, we aimed in this study to modulate CD4+TEM cell activity via Kv1.3 blockade using the specific peptide inhibiter, ShK-186. METHODS: Peripheral blood samples from 27 patients with GPA in remission and 16 age- and sex-matched healthy controls (HCs) were pre-incubated in vitro in the presence or absence of ShK-186, followed by stimulation with phorbol myristate acetate, calcium ionophore and brefeldin-A. The effect of ShK-186 on the cytokine production (IFNγ, TNFα, IL-4, IL-17, IL-21) within total and subsets of CD4+ T helper (CD4+TH) cells were assessed using flow cytometry. RESULTS: ShK-186 reduced the expression level of IFNγ, TNFα, IL-4, IL-17 and IL-21 in CD4+TH cells from patients with GPA in vitro. Further analysis performed on sorted CD4+T cell subsets, revealed that ShK-186 predominantly inhibited the cytokine production of CD4+TEM cells. ShK-186 treatment reduced the production of the pro-inflammatory cytokines to the level seen in CD4+ TH cells from HCs. CONCLUSIONS: Modulation of cellular effector function by ShK-186 may constitute a novel treatment strategy for GPA with high specificity and less harmful side effects.

SERPINA3, FGA, AGP1, ITIH3 and SAA1 as novel biomarkers for eosinophilic granulomatosis with polyangiitis diagnosis and activity assessment.

OBJECTIVE: To identify novel biomarkers for diagnosis and prediction of active eosinophilic granulomatosis with polyangiitis (EGPA) through data-independent acquisition (DIA) analysis. METHODS: Plasma from 11 EGPA patients and 10 healthy controls (HCs) were analyzed through DIA to identify potential biomarkers. The results were validated in 32 EGPA patients, 24 disease controls (DCs), and 20 HCs using enzyme-linked immunosorbent assay (ELISA). The receiver operating characteristic (ROC) curve was used to assess the diagnostic value of candidate biomarkers. RESULTS: Thirty-five differentially expressed proteins (DEPs) (24 upregulated and 11 downregulated) were screened between EGPA and HC groups. Five proteins, including serine proteinase inhibitor A3 (SERPINA3), alpha-fibrinogen (FGA), alpha-1 acid glycoprotein 1(AGP1), inter-alpha-trypsin inhibitor heavy chain H3 (ITIH3), and serum amyloid A1 (SAA1), were significantly upregulated in EGPA compared with HCs. Apart from SAA1, all proteins were also higher in EGPA patients compared with DCs. Furthermore, a panel of SERPINA3 and SAA1 exhibited potential diagnostic value for EGPA with an area under the curve (AUC) of 0.953, while a panel of SERPINA3, FGA, AGP1, and ITIH3 showed good discriminative power to differentiate EGPA from DCs with AUC of 0.926. Moreover, SERPINA3, FGA, and AGP levels were significantly higher in active EGPA and correlated well with disease activity. A combination of SERPINA3 and AGP1 exhibited an excellent AUC of 0.918 for disease activity assessment. CONCLUSION: SERPINA3, FGA, AGP1, ITIH3 and SAA1 were identified as potential biomarkers for EGPA diagnosis and disease activity assessment. Among them, as a single biomarker, SERPINA3 has the best diagnostic performance.

Distinct features of ANCA-associated hypertrophic pachymeningitis compared to other etiologies: findings from a study of 74 patients.

OBJECTIVES: We aimed to characterize the clinical and radiological features, and outcomes, of a large cohort of hypertrophic pachymeningitis (HP) patients from a single center. METHODS: We conducted a retrospective study at a tertiary referral center, encompassing patients diagnosed with HP between 2003 and 2022. The diagnosis of HP relied on the identification of thickening of the dura mater via magnetic resonance imaging (MRI) of the brain or spine. RESULTS: We included 74 patients with a mean age of 43.6 ± 14.2 years, of whom 37 (50%) were male. Among them, 32 (43.2%) had an immune-mediated origin, including 21 with granulomatosis with polyangiitis (GPA) (predominantly PR3-ANCA positive), four with systemic lupus erythematosus, three with IgG4-related disease, three with idiopathic HP, and one with rheumatoid arthritis. Non-immune-mediated HP accounted for 45 cases (56.8%). Within this category, 21 (28.4%) were infectious cases, with 14 being Mycobacterium tuberculosis infection (TB-HP), and 21 (28.4%) were malignancy-associated HP. Clinical and MRI characteristics exhibited variations among the four etiological groups. Hypoglycorrhachia was primarily observed in infectious and malignancy-associated HP. Immune-mediated HP was associated with a peripheral pattern of contrast enhancement and the Eiffel-by-night sign. MRI features strongly indicative of TB-HP included leptomeningeal involvement, brain parenchymal lesions, and arterial stroke. MPO-ANCA GPA was associated with a higher prevalence of spinal HP. CONCLUSIONS: Within our cohort, GPA and Mycobacterium tuberculosis emerged as the predominant causes of HP. We identified significant disparities in clinical and radiological features among different etiologies, which could have implications for diagnosis.

Cardiac involvement in eosinophilic granulomatosis with polyangiitis: acute eosinophilic myocarditis and chronic inflammatory cardiomyopathy.

OBJECTIVES: Currently, cardiac involvement is used to describe all eosinophilic granulomatosis with polyangiitis (EGPA) cardiac problems. However, heterogeneity exists among them. We aimed to depict the disease spectrum of EGPA cardiac involvement and identify high-risk population. METHODS: We included EGPA patients hospitalized in our center from 2012 to 2023 and in public databases. Based on the cardiac enzymes, cardiac magnetic resonance imaging, and endomyocardial biopsy results, the patients were divided into 3 groups: eosinophilic myocarditis (EGPA-EM), chronic inflammatory cardiomyopathy (EGPA-ICM) and EGPA-Control. Their clinical, laboratory, imaging results and prognoses were collected and compared. RESULTS: A total of 193 EGPA patients were included, 118 with cardiac involvement (74 EGPA-EM, 44 EGPA-ICM) and 75 control. Among EGPA-control, EGPA-ICM and EGPA-EM, eosinophil increased (6.12/8.71/10.42 × 109/l, p< 0.01), ANCA positivity decreased (41.33/31.82/14.86%, p< 0.01), and lung involvement reduced (73.33/72.73/43.24%, p= 0.02). In EGPA-EM, cardiac troponin further elevated (0.27 vs 6.00 ng/ml, p< 0.01), ejection fractions decreased (57.79 vs 33.20%, p< 0.01), while more ST-T abnormality was observed (41.89 vs 20.45%, p= 0.02). The prognosis of EGPA-EM was significantly worse, with 14.86% death rate, and 2-year event-free survival rate below 50%. Further, we proposed a LATE-EAST diagnostic score (7 items, 9 points) to discriminate EGPA-EM from EGPA-ICM using 4 points as threshold [AUC 0.85 (95%CI 0.78-0.92), sensitivity 0.78, specificity 0.86]. CONCLUSIONS: We first proposed different subtypes of cardiac involvement in EGPA. Identification and treatment of EGPA-EM needs improvement. LATE-EAST score could recognize the high-risk EGPA-EM effectively. Multi-disciplinary treatment is warranted, immunosuppressive therapy should be given timely and anti-IL-5 antibodies be tested in trials.

Association between CBL gene polymorphism and susceptibility of microscopic polyangiitis in a Chinese population: A case-control analysis.

OBJECTIVE: To assess whether Casitas B-lineage lymphoma (CBL) gene polymorphism influences the risk of microscopic polyangiitis (MPA) in Chinese populations. METHODS: In total, 266 MPA patients and 297 healthy controls were recruited for a case-control study. Five CBL SNPs were genotyped using multiplex polymerase chain reaction and high-throughput sequencing. The relationship between SNPs and the risk of MPA under different genetic models was evaluated by SNPstats. SNP-SNP interaction was analyzed by generalized multifactor dimensionality reduction (GMDR). Finally, the association between CBL SNPs and treatment effects were assessed. RESULTS: The results showed that CBL rs2276083 was associated with decreasing MPA risk under dominant (OR: 0.53; p = 0.014) and recessive models (OR: 0.52; p = 0.0034). Stratification analysis indicated that rs2276083 and rs2509671 in age < 60 years, rs2276083 in female or in Han population were protective factors for MPA. The CBL haplotype (A-A-G-C-T) was associated with an increased risk of MPA. GMDR suggested that CBL rs2276083, phosphatidylinositol-4, 5-bisphosphate 3-kinase catalytic subunit alpha (PI3KCA) rs1607237, and autophagy-related gene 7 (ATG7) rs7549008 might interact with each other in MPA development (p = 0.0107). CBL rs1047417 with AG genotype and rs11217234 with AG genotype had better clinical treatment effects than other two genotypes (p = 0.048 and p = 0.025, respectively). CONCLUSION: The genetic polymorphism of CBL had a potential association with the risk of MPA and clinical treatment effects in Guangxi population in China.

Tezepelumab for refractory eosinophilic granulomatosis with polyangiitis-related asthma.

Conventional immunosuppressants are ineffective for the management of EGPA-related asthma. Tezepelumab is a human monoclonal antibody that inhibits thymic stromal lymphopoietin (TLSP) that has proven efficacy in several phase 3 studies for the treatment of asthma. We treated with off-label tezepelumab the first two patients with severe refractory EPGA-related asthma. These preliminary findings suggest that targeting upstream signaling of the T2 inflammatory pathway can improve symptoms, reduce BVAS and increase Asthma Control Test scores, even in patients with refractory asthma who have failed several previous lines of treatment. Nevertheless, by analogy with dupilumab-induced IL-4/13 blockade, the persistence of sputum eosinophilia (reported in both patients) raises questions as to whether TSLP inhibition could lead to a rebound of eosinophilia and potentially to eosinophil-related symptoms in patients with EGPA.

Factors Affecting the Ability to Discontinue Oral Corticosteroid Use in Patients with EGPA Treated with Anti-Interleukin-5 Therapy.

INTRODUCTION: Patients with eosinophilic granulomatosis with polyangiitis (EGPA) and some with severe eosinophilic asthma require continuous long-term oral corticosteroid (OCS) treatment for disease control. The anti-interleukin-5 agent, mepolizumab, has recently become available for the treatment of severe eosinophilic asthma and EGPA, with promising results and safety profiles. The proportion of patients with EGPA who discontinued oral steroids was 18% in the MIRRA trial. To compare patients with EGPA who were able to discontinue steroids with mepolizumab with those who could not. METHODS: Twenty patients with EGPA treated with mepolizumab were evaluated at Osaka Habikino Medical Center. The OCS dose, asthma control test score, fractional exhaled nitric oxide levels, peripheral eosinophil count, and spirometric parameters were evaluated before and after treatment. RESULTS: There was a significant reduction in the mean OCS dose from a prednisolone equivalent of 8.88 ± 4.99 mg/day to 3.18 ± 3.47 mg/day (p < 0.001). In this study, 40% of patients discontinued oral steroids. The most common reason for the failure to discontinue steroids in patients was poor asthma control. The percentage of predicted forced expiratory volume in 1 s significantly improved in patients with EGPA who could discontinue steroids after receiving mepolizumab. CONCLUSION: In this real-world study, treatment with mepolizumab for EGPA was associated with a significant reduction in OCS use; however, poor asthma control was identified as an inhibiting factor for steroid reduction.

Classification Criteria for ANCA Associated Vasculitis - Ready for Prime Time?

PURPOSE OF REVIEW: This review aims to summarize the evolution and recent developments in the classification of ANCA associated vasculitis (AAV) and to summarize evaluations of the 2022 ACR/EULAR classification criteria of AAV in several cohorts. RECENT FINDINGS: The classification of AAV has been a field of controversy for some time. The parallel existence of classification criteria and disease definitions produced some overlap in classification, leading to challenges when comparing different cohorts. The 2022 ACR/EULAR classification criteria derived from the largest study ever conducted in vasculitis account for significant changes in vasculitis classification with the integration of ANCA and modern imaging. These criteria show good performance compared to previous ones but also raise questions as ANCA serotypes have substantial impact on classification. In addition, there are some discrepancies with earlier agreed histopathological features of AAV disease phenotypes. During the last 35 years, several sets of classification criteria have evolved to facilitate epidemiologic studies and clinical trials in AAV. While some of these criteria have been in use for many years, they were criticized due to either not using ANCA or not integrating surrogate markers for vasculitis but also due to overlapping when used in parallel. The long-awaited new ACR/EULAR criteria for AAV were published in 2022 and are the result of a large international study, introducing for the first time ANCA and modern imaging in the classification of AAV. Though the criteria show good performance, they bring several other challenges with practical application.

Renal damage and old age: risk factors for thrombosis in patients with ANCA-associated vasculitis.

INTRODUCTION: Thrombosis in ANCA-associated vasculitis (AAV) was prevalent and has been neglected in Chinese patients. This study tried to describe the clinical characteristics, identify the risk factors, and investigate the causal relationship between AAV and venous thromboembolism (VTE) by two-sample Mendelian randomization (MR) analysis. METHODS: In this retrospective, observational study, we included all hospitalized AAV patients from Jan 2013 to Apr 2022 in Peking Union Medical College Hospital. We collected their clinical data for multivariate regression analysis to determine the risk factors for thrombosis. The nomogram was constructed by applying these risk factors to predict thrombosis in AAV patients. As for MR analysis, we selected single nucleotide polymorphisms (SNPs) related to AAV from published genome-wide association studies and extracted the outcome data containing deep vein thrombosis (DVT) and pulmonary embolism (PE) from the UK biobank. RESULTS: 1203 primary AAV patients were enrolled, and thrombosis occurred in 11.3%. Multivariate regression suggested that older than 65 years, EGPA, neurological involvement, lung involvement, significantly elevated serum creatinine (> 500µmol/L), and elevated D-dimer were associated with thrombosis in AAV patients. The model demonstrated satisfied discrimination with an AUC of 0.769 (95% CI, 0.726-0.812). MR analysis showed that EGPA could increase the risk of developing DVT and PE (OR = 1.0038, 95%CI = 1.0035-1.0041, P = 0.009). CONCLUSION: Thrombosis was not rare in Chinese patients with AAV. Renal damage and old age emerged as critical risk factors for thrombosis. EGPA might have a potential causal relationship with DVT and PE.