The role of tobacco smoking in anti-neutrophil cytoplasmic antibody-associated vasculitis: a systematic review.

OBJECTIVES: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are a group of systemic pauci-immune necrotising vasculitides involving small vessels, characterised by the presence of specific ANCA autoantibodies directed to leukocyte proteinase 3 (PR3-ANCA) or myeloperoxidase (MPO-ANCA) and subdivided into three clinical entities: granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (EGPA). The aetiology of AAV is unknown and many genetic, epigenetic and environmental factors have been reported to be involved in pathogenesis. Smoking is widely recognised as a risk factor for the development of many autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus. This systematic review will analyse known data about the role of smoking in the development, clinical presentation and outcome of AAV. METHODS: Articles that examined interactions between tobacco smoking and AAV (GPA, MPA, EGPA) were included. All articles selected were in English. No limitation on publication date was established. Case reports were excluded. The systematic search was performed using PubMed/Medline and Cochrane Library databases. RESULTS: The search provided a total of 131 articles. Three studies were added, obtained from the review of the reference lists of articles. 70 were removed because they were duplicated or written in languages other than English. The title and abstract of 64 articles were screened. Of these, 30 were excluded as the title and/or abstract did not meet the inclusion criteria. Thus, 34 remained for full-text review, of which 8 were excluded. 26 articles were therefore included in this review. The role of smoking in AAV development is unclear. AAV patients current smoking appear appear to be younger and more frequently males, with a lower prevalence of EGPA and MPA than GPA. Ever smokers show higher relapse rate. Smoking seems to be associated with a higher risk of cardiovascular events during follow-up. Smokers incur an increased risk of infections. Finally, many data support smoking as a risk factor for end stage renal disease and mortality in AAV patients. CONCLUSIONS: Current data support the hypothesis that smoking influences prevalence, clinical phenotype and prognosis of ANCA-associated vasculitis. However, further studies are required to fully determine its role.

Granulomatosis with polyangiitis following Pfizer-BioNTech COVID-19 vaccination.

We report the first case of proteinase 3-antineutrophil cytoplasmic antibody-positive granulomatosis with polyangiitis (GPA) with predominant ears, nose, and throat manifestations following coronavirus disease 2019 (COVID-19) vaccination. A 63-year-old woman presented with aural fullness 3 days after vaccination. She presented with progressive rhinosinusitis and otitis media leading to profound hearing loss within 3 weeks. Clinical imaging revealed soft-tissue shadows in the paranasal sinuses with multiple pulmonary nodules, and histopathology was consistent with a diagnosis of GPA. It is crucial to be wary of the possibility of GPA in patients who received COVID-19 vaccines due to its rapid disease progression.

Defective STAT5 Activation and Aberrant Expression of BCL6 in Naive CD4 T Cells Enhances Follicular Th Cell-like Differentiation in Patients with Granulomatosis with Polyangiitis.

Granulomatosis with polyangiitis (GPA) is a potentially fatal small vessel vasculitis of unknown etiology, characterized by anti-neutrophil cytoplasmic autoantibodies, chronic inflammation, and granulomatous tissue damage. T cell dysregulation, comprising decreased regulatory T cell function and increased circulating effector memory follicular Th cells (TFH), is strongly associated with disease pathogenesis, but the mechanisms driving these observations are unknown. We undertook transcriptomic and functional analysis of naive CD4 T cells from patients with GPA to identify underlying functional defects that could manifest in the pathogenic profiles observed in GPA. Gene expression studies revealed a dysregulation of the IL-2 receptor ß/JAK-STAT signaling pathway and higher expression of BCL6 and BCL6-regulated genes in GPA naive CD4 T cells. IL-2-induced STAT5 activation in GPA naive CD4 T cells was decreased, whereas STAT3 activation by IL-6 and IL-2 was unperturbed. Consistently, BCL6 expression was sustained following T cell activation of GPA naive CD4 T cells and in vitro TFH differentiation of these cells resulted in significant increases in the production TFH-related cytokines IL-21 and IL-6. Thus, naive CD4 T cells are dysregulated in patients with GPA, resulting from an imbalance in signaling equilibrium and transcriptional changes that drives the skewed pathogenic CD4 effector immune response in GPA.

Granulomatous Inflammation in ANCA-Associated Vasculitis.

ANCA-associated vasculitis (AAV) comprises granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). While systemic vasculitis is a hallmark of all AAV, GPA is characterized by extravascular granulomatous inflammation, preferentially affecting the respiratory tract. The mechanisms underlying the emergence of neutrophilic microabscesses; the appearance of multinucleated giant cells; and subsequent granuloma formation, finally leading to scarred or destroyed tissue in GPA, are still incompletely understood. This review summarizes findings describing the presence and function of molecules and cells contributing to granulomatous inflammation in the respiratory tract and to renal inflammation observed in GPA. In addition, factors affecting or promoting the development of granulomatous inflammation such as microbial infections, the nasal microbiome, and the release of damage-associated molecular patterns (DAMP) are discussed. Further, on the basis of numerous results, we argue that, in situ, various ways of exposure linked with a high number of infiltrating proteinase 3 (PR3)- and myeloperoxidase (MPO)-expressing leukocytes lower the threshold for the presentation of an altered PR3 and possibly also of MPO, provoking the local development of ANCA autoimmune responses, aided by the formation of ectopic lymphoid structures. Although extravascular granulomatous inflammation is unique to GPA, similar molecular and cellular patterns can be found in both the respiratory tract and kidney tissue of GPA and MPA patients; for example, the antimicrobial peptide LL37, CD163+ macrophages, or regulatory T cells. Therefore, we postulate that granulomatous inflammation in GPA or PR3-AAV is intertwined with autoimmune and destructive mechanisms also seen at other sites.

CD8+ T Cells in GCA and GPA: Bystanders or Active Contributors?

Vasculitis refers to inflammation of blood vessels and can cause a variety of serious complications depending on which vessels are affected. Two different forms of vasculitis are Giant Cell Arteritis (GCA) and Granulomatosis with Polyangiitis (GPA). GCA is the most common form of vasculitis in adults affecting the large arteries and can lead to visual impairment and development of aneurysms. GPA affects small- and medium-sized blood vessels predominantly in the lungs and kidneys resulting in organ failure. Both diseases can potentially be fatal. Although the pathogenesis of GCA and GPA are incompletely understood, a prominent role for CD4+ T cells has been implicated in both diseases. More recently, the role of CD8+ T cells has gained renewed interest. CD8+ T cells are important players in the adaptive immune response against intracellular microorganisms. After a general introduction on the different forms of vasculitis and their association with infections and CD8+ T cells, we review the current knowledge on CD8+ T-cell involvement in the immunopathogenesis of GCA and GPA focusing on phenotypic and functional features of circulating and lesional CD8+ T cells. Furthermore, we discuss to which extent aging is associated with CD8+ T-cell phenotype and function in GCA and GPA.

Clinical Features of Patients with Active Eosinophilic Granulomatosis with Polyangiitis Successfully Treated with Mepolizumab.

BACKGROUND: In some patients with eosinophilic granulomatosis with polyangiitis (EGPA), remission cannot be induced, despite treatment with corticosteroids and immunosuppressants. We evaluated the clinical features of patients with EGPA in whom mepolizumab was effective. METHODS: There were 59 EGPA patients treated at Hiratsuka City Hospital, Japan, between April 2018 and September 2020, and 30 of them received mepolizumab. Twenty (66.7%) experienced a "marked effect" (the daily dose of corticosteroid or immunosuppressant could be decreased, or the interval between intravenous immunoglobulin (IVIG) treatments could be prolonged) and 10 (33.3%) experienced a "weak effect" (these measures were not achieved). Eosinophil numbers, serum IgG levels, daily doses of corticosteroids and immunosuppressants, and the interval between IVIG treatments at diagnosis and before and after mepolizumab initiation were determined. RESULTS: Eosinophil numbers at diagnosis were significantly higher in the marked-effect group than in the weak-effect group (p < 0.05) but not before mepolizumab initiation or at the last visit. Birmingham Vasculitis Activity Scores (BVASs) before mepolizumab initiation (p < 0.05) and at last visit (p < 0.01), and frequency of relapse before treatment initiation (p < 0.05) were significantly higher, and the serum IgG level before mepolizumab treatment was significantly lower in the weak-effect group than in the marked-effect group. The weak-effect group received higher doses of corticosteroids, even if the corticosteroid dose could be reduced for a while after mepolizumab initiation. CONCLUSION: High peripheral blood eosinophil numbers at EGPA diagnosis were suggestive of a positive clinical response to mepolizumab.

COVID-19-induced granulomatosis with polyangiitis.

COVID-19 and granulomatosis with polyangiitis share many clinical and radiological features, making it challenging for clinicians to distinguish between the two. In this case report, we describe a patient who was diagnosed with COVID-19 in October 2020. One month later, she presented with persistent fatigue, shortness of breath and anaemia with worsening renal functions, found to have elevated antineutrophil cytoplasmic antibodies and antiproteinase 3 antibodies, and diagnosed with granulomatosis with polyangiitis.

Increased Circulating Cell-Free DNA in Eosinophilic Granulomatosis With Polyangiitis: Implications for Eosinophil Extracellular Traps and Immunothrombosis.

Background: Endogenous DNA derived from nuclei or mitochondria is released into the blood circulation as cell-free DNA (cfDNA) following cell damage or death. cfDNA is associated with various pathological conditions; however, its clinical significance in antineutrophil cytoplasmic antibody-associated vasculitis (AAV) remains unclear. This study aimed to evaluate the clinical significance of cfDNA in AAV. Methods: We enrolled 35 patients with AAV, including 10 with eosinophilic granulomatosis with polyangiitis (EGPA), 13 with microscopic polyangiitis, and 12 with granulomatosis with polyangiitis. Serum cf-nuclear DNA (cf-nDNA) and cf-mitochondrial DNA (cf-mtDNA) levels were measured by quantitative polymerase chain reaction before and after the initiation of immunosuppressive therapy. Tissue samples from EGPA patients were examined by immunofluorescence and transmission electron microscopy. The structure of eosinophil extracellular traps (EETs) and neutrophil extracellular traps (NETs) and stability against DNase were assessed in vitro. Platelet adhesion of EETs were also assessed. Results: Serum cf-nDNA and cf-mtDNA levels were significantly higher in AAV than in healthy controls, with the highest levels in EGPA; however, serum DNase activities were comparable among all groups. cf-nDNA and cf-mtDNA decreased after treatment and were associated with disease activity only in EGPA. Blood eosinophil count and plasma D-dimer levels were significantly correlated with cf-nDNA in EGPA and cf-mtDNA. EGPA tissue samples showed lytic eosinophils and EETs in small-vessel thrombi. The structure of EETs showed bolder net-like chromatin threads in vitro and EETs showed greater stability against DNase than NETs. EETs provided a scaffold for platelet adhesion. Conclusion: cfDNA was increased in EGPA, associated with disease activity. The presence of DNase-resistant EETs in small-vessel thrombi might contribute to higher concentration of cfDNA and the occurrence of immunothrombosis in EGPA.

Non-specific orbital inflammation: Current understanding and unmet needs.

Non-specific orbital inflammation (NSOI) is a noninfectious inflammatory condition of the orbit. Although it is generally considered the most common diagnosis derived from an orbital biopsy, it is a diagnosis of exclusion, meaning that the diagnosis requires exclusion of a systemic process or another identifiable etiology of orbital inflammation. The clinical diagnosis of NSOI is ill-defined, but it is typically characterized by acute orbital signs and symptoms, including pain, proptosis, periorbital edema, chemosis, diplopia, and less commonly visual disturbance. NSOI poses a diagnostic and therapeutic challenge: The clinical presentations and histological findings are heterogeneous, and there are no specific diagnostic criteria or treatment guidelines. The etiology and pathogenesis of NSOI are poorly understood. Here we recapitulate our current clinical understanding of NSOI, with an emphasis on the most recent findings on clinical characteristics, imaging findings, and treatment outcomes. Furthermore, gene expression profiling of NSOI and its implications are presented and discussed.

Are Farming and Animal Exposure Risk Factors for the Development of Granulomatosis With Polyangiitis? Environmental Risk Factors Revisited: A Case-control Study.

OBJECTIVE: To investigate the possible association between animal exposure and risk for granulomatosis with polyangiitis (GPA). METHODS: Patients with GPA at the Department of Rheumatology, Uppsala University Hospital, between January 1, 2011, and December 31, 2018, were consecutively included. All patients filled in a questionnaire on possible environmental exposures: occupation, hobbies, and animal contact. As controls we included 128 patients with rheumatoid arthritis (RA) and 248 population controls collected from the Epidemiological Investigation of Rheumatoid Arthritis (EIRA) study, matched for age, sex, and geographical area of residence. The controls filled out a questionnaire on current and past contact with farming and animals, at the time of the RA patient's diagnosis. RESULTS: A total of 62 patients with GPA, 128 patients with RA, and 248 population controls were included in the study. GPA was significantly associated with horse exposure, with a 2- to 3-fold increased risk compared with RA (OR 3.08, 95% CI 1.34-7.08) and population controls (OR 2.61, 95% CI 1.29-5.29). Borderline increased risks were found for any animal contact, but no association was found when analyzing contact with cats/dogs only. A significant association was found between GPA and farming compared to the population controls (OR 7.60, 95% CI 3.21-17.93). CONCLUSION: This study has identified for the first time, to our knowledge, a significant association between exposure to specific animals, namely horses, and the development of GPA. The results also support previous studies reporting an association between farming and GPA, underscoring the possibility of exogenous factors as initiators in the development of GPA.

Disseminated Saksenaea infection in an immunocompromised host associated with a good clinical outcome: a case report and review of the literature.

BACKGROUND: Saksenaea species (spp.) are uncommon causes of mucormycosis but are emerging pathogens mostly associated with trauma and soil contamination often in immunocompetent hosts. Due to lack of sporulation in the laboratory, diagnosis and susceptibility testing is difficult so optimal treatment regimens are unknown. CASE PRESENTATION: A 67 year-old man from the Northern Territory in Australia, with a history of eosinophilic granulomatosis with polyangiitis, developed disseminated Saksenaea infection after initially presenting with symptoms consistent with bacterial pyelonephritis. Despite a delay in diagnosis; with aggressive surgical management and dual therapy with amphotericin B and posaconazole, he survived. CONCLUSIONS: We describe an unusual case of disseminated infection with a favourable outcome to date.

A case of eosinophilic granulomatosis with polyangiitis as a mimicker of IgG4-related disease.

A 62-year-old woman was admitted to our hospital because of fever, renal dysfunction, eosinophilia, and the presence of MPO-ANCA. Based on the renal pathological examination which showed granuloma lesion with eosinophils and crescentic glomerulonephritis, eosinophilic granulomatosis with polyangiitis (EGPA) was diagnosed. On the other hand, laboratory examination showed elevated serum IgG4 levels and renal pathological examination showed marked lymphoplasmacytic infiltration and fibrosis surrounding nest "Bird's eye pattern," which were characteristic of IgG4-related kidney disease (IgG4-RKD). Because there are cases when EGPA has clinical features of IgG4-RKD, we should be careful about diagnoses of IgG4-RKD in patients with EGPA.

Cocaïne et lésions destructrices centro-faciales : à propos d'un cas.

INTRODUCTION: Cocaine use is associated with multiple complications, some of which can mimic systemic diseases, especially Antineutrophil Cytoplasmic Antibody (ANCA) associated vasculitis. We report a case of Cocaine Induced Midline Destructive Lesions (CIMDL) for which a diagnosis of granulomatosis with polyangiitis (GPA) was discussed. CASE REPORT: A 42-year-old male, cocaine consumer, was admitted in our department for a centrofacial destructive process. He had no extra ear, nose and throat (ENT) involvement. ANCA were positive with a perinuclear fluorescence pattern and an anti-Proteinase 3 specificity. Regarding this unusual immunologic pattern and in the absence of histological argument for a GPA, a diagnosis of CIMDL was made. CONCLUSION: CIMDL is a centrofacial destructive process due to intranasal cocaine use. It is frequently associated with the presence of p-ANCA with both anti-HNE and anti-PR3 specificity.

Complement profile in microscopic polyangiitis and granulomatosis with polyangiitis: analysis using sera from a nationwide prospective cohort study.

OBJECTIVE: The complement cascade, especially the alternative pathway of complement, has been shown in basic research to be associated with anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV). We aimed to elucidate relationships between serum complement components and clinical characteristics in AAV. METHOD: In a nationwide prospective cohort study (RemIT-JAV-RPGN), we measured the serum levels of C1q, C2, C3, C3b/iC3b, C4, C4b, C5, C5a, C9, factor B, factor D, factor H, factor I, mannose-binding lectin, and properdin in 52 patients with microscopic polyangiitis (MPA) and 39 patients with granulomatosis with polyangiitis (GPA). RESULTS: The properdin level of MPA and GPA was significantly lower than that of healthy donors. The properdin level was negatively correlated with the Birmingham Vasculitis Activity Score (BVAS) (ρ = -0.2148, p = 0.0409). The factor D level at 6 months was significantly positively correlated with the Vasculitis Damage Index (VDI) at 6, 12, and 24 months (ρ = 0.4207, 0.4132, and 0.3115, respectively). Patients with a higher ratio of C5a to C5 had higher neutrophil percentage and serum immunoglobulin G levels, and significantly lower creatinine levels. Cluster analysis divided the MPA and GPA patients into three subgroups. A principal component (PC) analysis aggregated 15 types of complements into alternative pathway-related PC 1 and complement classical pathway and common pathway-related PC 2. CONCLUSIONS: The serum levels of properdin and factor D were correlated with the BVAS and the VDI in MPA and GPA, respectively. Our analyses suggested the pathological heterogeneity of MPA and GPA from the aspect of complement components.

Localised granulomatosis with polyangiitis in an older patient with rheumatoid arthritis.

New onset of granulomatosis with polyangiitis (GPA) occurring in patients previously diagnosed with rheumatoid arthritis (RA) is very uncommon. In older individuals, this condition is associated with high mortality, especially in those with renal involvement. We describe the first case of GPA in a patient older than 65 years diagnosed with RA without exposure to biologic disease-modifying anti-rheumatic drugs, presenting with pulmonary nodules due to a limited form of anti-neutrophil cytoplasmic antibody-negative GPA.

Idiopathic Orbital Pseudotumor Preceding Systemic Inflammatory Disease in Children.

PURPOSE: To describe four pediatric cases in which isolated orbital pseudotumor preceded the development of a systemic inflammatory disease by months to years. METHODS: The medical records of all patients with the clinical diagnosis of orbital pseudotumor seen at the Ocular Oncology Service of Wills Eye Hospital and Northern Virginia Ophthalmology Associates from 2010 to 2015 were reviewed retrospectively, and those associated with systemic inflammatory disease were selected for further study. Data were retrospectively collected from medical record review regarding patient demographics and clinical features, time to development of systemic inflammatory disease, and medical management. RESULTS: In four pediatric patients, isolated orbital pseudotumor preceded the development of a systemic inflammatory disease, including pauciarticular juvenile idiopathic arthritis, eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome), granulomatosis with polyangiitis (Wegener's granulomatosis), and Crohn's disease. CONCLUSIONS: Orbital pseudotumor may be an antecedent to systemic inflammatory disease in children. Because this was a small case series, the authors are not ready to suggest that a full systemic work-up for systemic inflammatory disease is warranted for every patient with orbital pseudotumor. However, close observation and suspicion for systemic inflammatory conditions may be reasonable in children who present with idiopathic orbital pseudotumor. [J Pediatr Ophthalmol Strabismus. 2019;56(6):373-377.].

Neutrophil extracellular traps generation and degradation in patients with granulomatosis with polyangiitis and systemic lupus erythematosus.

Neutrophils are one of the first cells to arrive at the site of infection, where they apply several strategies to kill pathogens: degranulation, respiratory burst, phagocytosis, and release of neutrophil extracellular traps (NETs). Recent discoveries try to connect NETs formation with autoimmune diseases, like systemic lupus erythematosus (SLE) or granulomatosis with polyangiitis (GPA) and place them among one of the factors responsible for disease pathogenesis. The aim of the study was to assess the NETotic capabilities of neutrophils obtained from freshly diagnosed autoimmune patients versus healthy controls. Further investigation involved assessing NETs production among treated patients. In the latter step, NETs degradation potency of collected sera from non-treated patients was checked. Lastly, the polymorphisms of the DNASE I gene among tested subjects were checked. NETs formation was measured in a neutrophil culture by fluorometry, while degradation assessment was performed with patients' sera and extracellular source of DNA. Additionally, Sanger sequencing was used to check potential SNP mutations between patients. About 121 subjects were enrolled into this study, 54 of them with a diagnosed autoimmune disorder. Neutrophils stimulated with NETosis inducers were able to release NETs in all cases. We have found that disease affected patients produce NETs more rapidly and in larger quantities than control groups, with up to 82.5% more released. Most importantly, we showed a difference between the diseases themselves. NETs release was 68.5% higher in GPA samples when compared to SLE ones while stimulated with Calcium Ionophore. Serum nucleases were less effective at degrading NETs in both autoimmune diseases, with a reduction in degradation of 20.9% observed for GPA and 18.2% for SLE when compared with the controls. Potential therapies targeting neutrophils and NETs should be specifically tailored to the type of the disease. Since there are significant differences between NETs release and disease type, a standard neutrophil targeted therapy could prevent over-generation of traps in some cases, while in others it would deplete the cells, leaving the immune system unresponsive to primary infections.

Update on eosinophilic granulomatosis with polyangiitis.

Eosinophilic granulomatosis with polyangiitis (EGPA) (formerly Churg-Strauss syndrome) is a rare form of anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis characterized by eosinophil-rich granulomatous inflammation and small to medium-size vessel vasculitis associated with bronchial asthma and eosinophilia. Its rarity and unique features such as eosinophilic inflammation have delayed progress of research regarding EGPA for several years, compared to other forms of ANCA-associated vasculitis. However, recently, attention to EGPA as a research subject has been gradually increasing. To resolve problems in existing criteria for EGPA, new classification criteria for EGPA generated by a large international cohort will be launched and is being expected to accelerate future studies. Pathogenesis and roles of ANCA in EGPA are still largely unknown; however, it has been reported that glomerulonephritis is more frequent in ANCA-positive patients than in ANCA-negative patients, while heart failure is more frequent in ANCA-negative patients than in ANCA-positive patients. In addition, a recent genome-wide association study has suggested the presence of two genetically distinct subgroups of EGPA, which correspond to ANCA-positive and -negative subgroups. Although responses to glucocorticoids in EGPA are generally good, patients with EGPA often experience a relapse. Currently, there is no standard therapy for EGPA based on accumulation of clinical trial results. Recently, clinical benefits of mepolizumab for EGPA were proved by a randomized controlled trial and mepolizumab was approved for EGPA. In addition, various new drugs are under evaluation. To find optimal use of these drugs and to resolve unmet needs, such as relapse prevention, will be needed in future.