Eosinophilic granulomatosis with polyangiitis: an overview

Aural Manifestations of Antineutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis-Diagnosis, Symptoms, Treatment

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of vasculitis sharing a common pathophysiology, which affects small and medium blood vessels. There are three categories of AAV: granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). As a systemic disease, AAV can affect basically every organ. The goal of this publication is to sum up and underline the problem of the aural manifestation of AAV; it details the definition of Otitis Media with Antineutrophil Cytoplasmic Antibody Associated Vasculitis (OMAAV) and allows for a better understanding of the specific tasks of medical professionals taking part in the diagnostic and therapeutic process. Among others, this publication is directed to otolaryngologists who may encounter patients with AAV and often are the first specialists who see patients with early symptoms of AAV. This publication presents brief characteristics of AAV, descriptions of aural manifestations and symptoms, differential diagnosis, and both pharmacological and surgical treatment options, based on current recommendations and information found in the literature and clinical databases.

Burden of eosinophilic granulomatosis with polyangiitis in Europe

Background and aims

Real-world evidence characterising the burden of eosinophilic granulomatosis with polyangiitis (EGPA) in Europe is limited. The aim of this study was to characterise patients in a large European EGPA cohort.

Methods

This retrospective, non-interventional, longitudinal study (GSK ID: 214661) recruited cross-specialty physicians from France, Germany, Italy, Spain and the UK to conduct medical chart reviews for patients with a physician-confirmed diagnosis of EGPA. Patients were ≥12 years of age at diagnosis with ≥1 year of follow-up data from the first clinical visit with the physician (index date). Outcome measures collected from index date to end of follow-up included clinical manifestations and healthcare resource utilisation (HCRU).

Results

In total, 407 patient medical charts were reviewed by 204 physicians; median (interquartile range) duration of follow-up from index date was 2.2 (1.7-3.5) years. Most patients (73.5%) had asthma. Patients underwent multiple diagnostic assessments, and 74.9% received ≥3 different therapies between diagnosis and end of follow-up (98.8% oral corticosteroids, 63.9% immunosuppressive therapies, 45.5% biologics). During follow-up, 84.5% of patients experienced EGPA clinical manifestations; most were considered moderate or severe and commonly affected the lungs (55.8%; including lung infiltrates 25.8% and severe asthma 24.8%), ear, nose and throat (53.3%), and skin (41.8%). HCRU was substantial: 26.0% of patients made emergency department visits, 36.6% were hospitalised and 84.8% had outpatient visits.

Conclusions

These real-world data show that EGPA presents a substantial burden to patients and the healthcare system. Earlier and better differential diagnosis and appropriate treatment may help reduce incidence of clinical manifestations and HCRU.

Monocentric study of IL-5 monoclonal antibody induction therapy for eosinophilic granulomatosis with polyangiitis

OBJECTIVE

Although sporadic case reports have demonstrated successful management of eosinophilic granulomatosis with polyangiitis (EGPA) by anti-IL-5 therapy, larger-scale monocentric studies for the efficacy of mepolizumab (MEP), an IL-5 monoclonal antibody, are still lacking in Taiwan.

METHODS

Hospitalized EGPA patients aged at least 18 years were enrolled from November 1998 to October 2023, and analyzed for demographic, clinical, laboratory, medication and outcome data, focusing on the efficacy and safety of biologics use, particularly induction therapy with MEP.

RESULTS

Twenty-seven EGPA patients aged 10-70 years (43 ± 15) at disease diagnosis were recruited with 21 under combined corticosteroids/cyclophosphamide induction therapy. Seventeen patients received biologics with 13 under MEP therapy. Ten patients aged 19-71 years (48 ± 15) completed 12-month induction therapy with a 100 mg quadri-weekly subcutaneous injection regimen indicated for active or relapse disease. There were reduced BVAS with complete remission in 6 and partial remission in 4 patients, lower CRP levels, decreased eosinophil counts with an inhibition of 92∼96 %, and tapered prednisolone dosages from 5 to 25 (13.0 ± 6.3) to 0-10 (3.3 ± 3.1) mg/day. Only one patient had an adverse event of injection site reactions. Nine patients received the same regimen for annual maintenance therapy. All had a persistent clinical remission. In these patients, 13-56 injections (41 ± 15) were prescribed with a follow-up period of 12∼52 months (38 ± 14).

CONCLUSION

In this retrospective study, induction therapy with a 12-month 100 mg MEP quadri-weekly subcutaneous injection regimen demonstrates the efficacy and safety for active and relapsing EGPA patients.

Eosinophilic granulomatous polyangiitis with central nervous system involvement in children: a case report and literature review

Objective

To explore the clinical characteristics and treatment outcomes of children with central nervous system (CNS) involvement in eosinophilic granulomatosis with polyangiitis (EGPA).

Methods

A child who presented with EGPA complicated by CNS involvement was admitted to our hospital in June 2023. The clinical features were analyzed retrospectively, and relevant literatures were reviewed to provide a comprehensive overview of this condition.

Results

A ten-year-old girl, who had a history of recurrent cough and asthma accompanied by peripheral blood eosinophilia for eight months, was admitted to our hospital. On admission, spotted papules were visible on her hands and feet, bilateral pulmonary rales were audible. The laboratory examination revealed that the proportion of eosinophils (EOS) exceeded 10% of white blood cells, the anti-neutrophil cytoplasmic antibody (MPO-ANCA) was positive, the immunoglobulin G level was 15.80g/L, and the immunoglobulin E level was greater than 2500.00IU/mL. The imaging examination showed multiple patchy and nodular high-density shadows in both lungs as well as sinusitis. Pulmonary function tests indicated moderate ventilation and diffusion dysfunction. Bone marrow cytology demonstrated a significant increase in the proportion of eosinophils. Skin pathology confirmed leukocytoclastic vasculitis. During the hospitalization, the child had a convulsion. The magnetic resonance imaging (MRI) scan of the brain showed multiple abnormal signal shadows in the bilateral cerebral cortex and the electroencephalogram (EEG) showed epileptic waves. Following the administration of methylprednisolone pulse therapy in combination with cyclophosphamide treatment, her cough and asthma resolved, the skin rash disappeared without any further convulsions. We found that only a young EGPA patient with CNS involvement had been previously reported. The previously reported case began with long-term fever, weight loss, and purpuric rash. Both patients responded well to treatment with glucocorticoids and cyclophosphamide, experiencing significant improvement in their clinical symptoms and normalization of their peripheral blood eosinophils.

Conclusion

The diagnosis of EGPA in children can be challenging. When a child is affected by EGPA, it is essential to remain vigilant for signs of CNS involvement. The treatment with glucocorticoids and cyclophosphamide is effective in managing EGPA in children.

Pathogenesis of Pulmonary Manifestations in ANCA-Associated Vasculitis and Goodpasture Syndrome

Pulmonary manifestations of vasculitis are associated with significant morbidity and mortality in affected individuals. They result from a complex interplay between immune dysregulation, which leads to vascular inflammation and tissue damage. This review explored the underlying pathogenesis of pulmonary involvement in vasculitis, encompassing various forms such as granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), eosinophilic granulomatosis with polyangiitis (EGPA), and anti-GBM disease. Mechanisms involving ANCA and anti-GBM autoantibodies, neutrophil activation, and neutrophil extracellular trap (NETs) formation are discussed, along with the role of the complement system in inducing pulmonary injury. Furthermore, the impact of genetic predisposition and environmental factors on disease susceptibility and severity was considered, and the current treatment options were presented. Understanding the mechanisms involved in the pathogenesis of pulmonary vasculitis is crucial for developing targeted therapies and improving clinical outcomes in affected individuals.

Exploring the immunopathology of type 2 inflammatory airway diseases

Significant advancements have been achieved in understanding the roles of different immune cells, as well as cytokines and chemokines, in the pathogenesis of eosinophilic airway conditions. This review examines the pathogenesis of Chronic Rhinosinusitis with Nasal Polyps (CRSwNP), marked by complex immune dysregulation, with major contributions from type 2 inflammation and dysfunctional airway epithelium. The presence of eosinophils and the role of T-cell subsets, particularly an imbalance between Treg and Th17 cells, are crucial to the disease's pathogenesis. The review also investigates the pathogenesis of eosinophilic asthma, a unique asthma subtype. It is characterized by inflammation and high eosinophil levels, with eosinophils playing a pivotal role in triggering type 2 inflammation. The immune response involves Th2 cells, eosinophils, and IgE, among others, all activated by genetic and environmental factors. The intricate interplay among these elements, chemokines, and innate lymphoid cells results in airway inflammation and hyper-responsiveness, contributing to the pathogenesis of eosinophilic asthma. Another scope of this review is the pathogenesis of Eosinophilic Granulomatosis with Polyangiitis (EGPA); a complex inflammatory disease that commonly affects the respiratory tract and small to medium-sized blood vessels. It is characterized by elevated eosinophil levels in blood and tissues. The pathogenesis involves the activation of adaptive immune responses by antigens leading to T and B cell activation and eosinophil stimulation, which causes tissue and vessel damage. On the other hand, Allergic Bronchopulmonary Aspergillosis (ABPA) is a hypersensitive response that occurs when the airways become colonized by aspergillus fungus, with the pathogenesis involving activation of Th2 immune responses, production of IgE antibodies, and eosinophilic action leading to bronchial inflammation and subsequent lung damage. This analysis scrutinizes how an imbalanced immune system contributes to these eosinophilic diseases. The understanding derived from this assessment can steer researchers toward designing new potential therapeutic targets for efficient control of these disorders.

Eosinophilic Granulomatosis With Polyangiitis: A Case Report

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare form of necrotizing small-to-medium vessel vasculitis that can be associated with antineutrophil cytoplasmic antibody (ANCA) positivity, asthma, and eosinophilia. We present the case of a 65-year-old male with a past medical history of asthma who presented to the emergency department with bilateral upper and lower extremity paresthesias, as well as right foot drop, persisting for a two-week duration. His lab work revealed leukocytosis of 20.6 K/uL with 12.36 K/uL of absolute eosinophils as well as elevated inflammatory markers with an erythrocyte sedimentation rate of 32 mm/hr and CRP of 7.3 mg/dL. Both c-ANCA and p-ANCA titers were also elevated at 1:320. An eventual MRI of the entire spine did not reveal any neurologic or anatomic lesions to explain the patient's symptoms. CT imaging was also remarkable for airspace opacities involving the anterior right and bilateral lower posterior lung regions, as well as pansinusitis. A nerve biopsy showed axonopathy as well as evidence of healed vasculitis. Pulse dose steroids were started, which conferred benefits to the patient after other forms of treatment were unsuccessful. Given the rarity of EGPA, we think it is important to add new cases to the literature with a thorough discussion of the steps leading up to how the diagnosis was made.

An unusual cause of progressive dyspnoea, pulmonary nodules and pleural effusions

Eosinophilic granulomatosis with polyangiitis (EGPA) is part of the ANCA-associated vasculitides, although ANCA-negative presentations are not infrequent. Asthma, allergic rhinitis and peripheral eosinophilia are classic associations although pleural effusions are an uncommon manifestation of EGPA. We describe a 35-year old Caucasian adult with asthma who presented with progressive dyspnoea, cough, peripheral eosinophilia and imaging that showed pulmonary nodules with pleural effusions. Biopsy with histopathological review confirmed the diagnosis of EGPA with steroid therapy resulting in significant resolution of symptoms and imaging findings.

Extensive ischaemic colitis-like colonic lesions in eosinophilic granulomatosis with polyangiitis

Eosinophilic granulomatosis with polyangiitis is a rare, immune-mediated, multisystemic disorder belonging to the group of antineutrophil cytoplasmic antibody-associated vasculitides. Gastrointestinal symptoms are relatively common in patients with eosinophilic granulomatosis with polyangiitis, reportedly occurring in ∼22.3% of cases. Vasculitic necrotising lesions normally occur in the intestinal tract, and in the present case, the colonic lesions were remarkably severe and extensive. Pulse steroid therapy combined with cyclophosphamide improved the patient's condition without any serious complications, such as intestinal perforation.

Eosinophilic Granulomatosis With Polyangiitis Following COVID-19 Vaccination: A Case Report

The current emergence of the coronavirus disease 2019 (COVID-19) pandemic and the possible side effects of COVID-19 mRNA vaccination remain worrisome. Few cases of vaccination-related side effects, such as vasculitis, have been reported. Eosinophilic granulomatosis with polyangiitis (EGPA), also known as Churg-Strauss syndrome, is a type of vasculitis characterized by the histological richness of eosinophils, asthma, polyneuropathy, sinusitis, and skin or lung involvement. Here, we report the first case of new onset EGPA following COVID-19 vaccination in Korea. A 71-year old woman developed a skin rash and presented with progressive weakness of the upper and lower extremities after the BNT162b2 vaccination (Pfizer-BioNTech). She was diagnosed with EGPA and her symptoms improved after systemic steroid and immunosuppressant therapy. Although it is very rare, clinicians should be aware that EGPA may occur after COVID-19 vaccination.

ANCA-negative ANCA-associated vasculitis: pitfalls of the 'vasculitis screen'

Despite its recognition as an 'ANCA-associated vasculitis' (AAV), eosinophilic granulomatosis with polyangiitis (EGPA) is ANCA negative in up to 60% of cases. Herein, we report the case of a young man with a clinical syndrome highly suggestive of EGPA but with repeated negative ANCA serology, ultimately presenting with cardiac arrest before recognition of the primary systemic vasculitis, whereupon he received successful induction therapy with high dose glucocorticoids and cyclophosphamide. The case illustrates the importance of awareness of ANCA negative AAV among general physicians in order to minimise morbidity and mortality.

Eosinophilic Granulomatosis with Polyangiitis: Latest Findings and Updated Treatment Recommendations

Eosinophilic granulomatosis with polyangiitis (EGPA) causes necrotizing vasculitis and eosinophil-rich granulomatous inflammation in small- to medium-sized vessels, resulting in multiple organ damage. EGPA is classified as an antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, with myeloperoxidase-ANCA detected in approximately one-third of the patients. Conventional treatment of EGPA relies on systemic glucocorticoids (GCs) in combination with cyclophosphamide when poor prognostic factors are present; however, the dilemma between disease control and drug-related adverse effects has long been a challenge. Recent studies have revealed that the genetic background, pathophysiology, and clinical manifestations differ between ANCA-positive and ANCA-negative patients; however, mepolizumab, an interleukin (IL)-5 inhibitor, is effective in both groups, suggesting that the IL-5-eosinophil axis is deeply involved in the pathogenesis of both ANCA-positive and ANCA-negative EGPA. This review summarizes the latest knowledge on the pathophysiology of EGPA and focuses on the roles of eosinophils and ANCA. We then introduce the current treatment recommendations and accumulated evidence for mepolizumab on EGPA. Based on current unmet clinical needs, we discuss potential future therapeutic strategies for EGPA.

Eosinophilic Granulomatosis with Polyangiitis after mRNA-1273 SARS-CoV-2 Vaccine

During one of the worst global health crises, millions of people were vaccinated against SARS-CoV-2. In rare cases, new onset systemic inflammatory diseases were reported with temporal coincidence to the vaccination. We describe a case of severe Eosinophilic Granulomatosis with Polyangiitis (EGPA) in a young asthmatic woman, occurring after a second dose of the mRNA-1273 vaccine. She presented with multisystem EGPA with cardiac and central nervous system involvement, complicated by secondary immune thrombocytopenia (ITP). We review the reported cases of EGPA coinciding with SARS-CoV-2 mRNA vaccination. All potentially vaccine-related EGPA cases reported so far occurred within 14 days from immunization. EGPA is very rare with an incidence of 1:1,000,000 inhabitants, and the number of reported post-vaccination EGPA cases lies within the expected incidence rate for the period. While we cannot prove a causal relationship between the vaccine and EGPA onset, the temporal relationship with the vaccine immune stimulation is intriguing, in a disease occurring almost always in adults with asthma and/or chronic rhinosinusitis and driven by an aberrant Th2 lymphocyte activation with hypereosinophilia; nevertheless, cases of inflammatory diseases (IMIDs) emerging in the context of vaccination remain rare and the benefits of preventing severe COVID presentations with SARS-CoV-2 mRNA vaccines remain unquestionable.

Therapeutic Advances in Eosinophilic Granulomatosis with Polyangiitis

Eosinophilic granulomatosis with polyangiitis (EGPA) is an eosinophilic vasculitis that affects a variety of organ systems. Historically, glucocorticoids and a variety of other immunosuppressants were used to abrogate the inflammation and tissue injury associated with EGPA. The management of EGPA has evolved greatly during the last decade with the development of novel targeted therapeutics that have resulted in significantly improved outcomes for these patients, with many more novel targeted therapies emerging.

Benralizumab: A novel treatment for the cutaneous features of paediatric eosinophilic granulomatosis with polyangiitis (pEGPA)

Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic vasculitis presenting primarily with pulmonary and cutaneous features. The disease is typically seen in the fifth or sixth decade of life (1, 2). We report a case of EGPA in an adolescent who was successfully treated with the interleukin-5 (IL-5) receptor inhibitor, benralizumab.

Subclinical microvascular changes in ANCA-vasculitides: the role of optical coherence tomography angiography and nailfold capillaroscopy in the detection of disease-related damage

BACKGROUND

Both cardiovascular and complement-mediated disorders might lead to microvascular damages in anti-neutrophil cytoplasm autoantibodies (ANCA)-associated vasculitides (AAV). We aimed at investigating, for the first time, subclinical microvascular abnormalities with non-invasive techniques in AAV patients by analyzing both retinal and nailfold capillary changes. Retinal plexi were investigated using optical coherence tomography angiography (OCT-A), while nailfold capillary changes by video-capillaroscopy (NVC). Potential correlations between microvessels' abnormalities and disease damage were also explored.

METHODS

An observational study was conducted on consecutive patients who met the inclusion criteria of defined diagnosis of eosinophilic granulomatosis with polyangiitis (EGPA), granulomatosis with polyangiitis (GPA), and microscopic polyangiitis (MPA), age ≥ 18 ≤ 75 yrs, and no ophthalmological disorders. Disease activity was assessed by Birmingham Vasculitis Activity Score (BVAS), damage by Vasculitis Damage Index (VDI), and poorer prognosis by the Five Factor Score (FFS). Quantitative analysis of vessel density (VD) was performed by OCT-A in both superficial and deep capillary plexi. Figures and detailed analysis from NVC were performed for all subjects in the study.

RESULTS

Included AAV patients (n = 23) were compared with 20 age/sex-matched healthy controls (HC). Retinal VD in superficial whole and parafoveal plexi resulted significantly decreased in AAV compared to HC (P = 0.02 and P = 0.01, respectively). Furthermore, deep whole and parafoveal vessel density was strongly reduced in AAV than HC (P ≤ 0.0001 for both). In AAV patients, significant inverse correlations occurred between VDI and OCTA-VD in both superficial (parafoveal, P = 0.03) and deep plexi (whole, P = 0.003, and parafoveal P = 0.02). Non-specific NVC pattern abnormalities occurred in 82% of AAV patients with a similar prevalence (75%) in HC. In AAV, common abnormalities were edema and tortuosity in a comparable distribution with HC. Correlations between NVC changes and OCT-A abnormalities have not been described.

CONCLUSION

Subclinical microvascular retinal changes occur in patients with AAV and correlate with the disease-related damage. In this context, the OCT-A can represent a useful tool in the early detection of vascular damage. AAV patients present microvascular abnormalities at NVC, whose clinical relevance requires further studies.

A case of eosinophilic granulomatous polyangiitis with concurrent central and peripheral nervous system involvement

Eosinophilic granulomatous polyangiitis (EGPA) like other antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis has multisystemic involvement. It commonly manifests with prodromal pulmonary involvement as asthma, chronic sinusitis followed by systemic vasculitic complications associated with blood and tissue eosinophilia. Central nervous system manifestations at presentation are uncommon compared with peripheral nervous system involvement. Vasculitic neuropathy in EGPA commonly presents as mononeuritis multiplex but rarely as polyradiculopathy. Late onset EGPA often presents with systemic involvement, and early diagnosis is a key to prevent further complications. The neuropathy in late onset EGPA is often refractory to immunosuppression and corticosteroids treatment. We report a case of EGPA with late onset asthma presenting with acute infarct and demyelinating polyradiculoneuropathy that progressed with bulbar paralysis and profound dysautonomia. This illustrates simultaneous involvement of central and peripheral nervous system with EGPA. Autonomic dysfunction can occur in patients of EGPA with multisystem involvement, which may predict severe complications.

Is peripheral blood immunophenotyping useful to understand the etiology of Idiopathic Granulomatous?

BACKGROUND

The etiology of idiopathic granulomatous mastitis (IGM) has not been clearly established. However, autoimmunity has recently become popular in etiopathogenesis. We aimed to investigate the immunophenotyping of immune cells to help clarify the etiopathogenesis of the disease.

METHODS

Patients with IGM and healthy volunteers were included in the study. Patients were divided into active and remission groups based on their disease status. The ratios of total T cells, helper T cells, cytotoxic T cells, natural killer cells, regulatory T cells, and monocyte subtypes were measured using flow cytometry. In addition, age, complete blood count for leukocyte, lymphocyte, neutrophil, and eosinophil counts, and the smoking status of all volunteers were evaluated.

RESULTS

A total of 33 volunteers, including 11 patients with active IGM, 10 patients with remission IGM, and 12 healthy volunteers, were included in the study. The neutrophil, eosinophil, neutrophil/lymphocyte, and non-classical monocyte values were significantly higher in IGM patients than in healthy volunteers. Additionally, the CD4⁺ CD25⁺ CD127^- regulatory T cell was significantly lower in IGM patients than in healthy volunteers. Furthermore, neutrophil, neutrophil/lymphocyte ratio, CD4⁺ CD25⁺ CD127^- regulatory T cells, and non-classical monocytes showed significant differences when IGM patients were divided into active and remission groups. IGM patients had higher smoking rates, but this was not statistically significant.

CONCLUSION

The changes in many cell types evaluated in our study were similar to the cell profiles of some autoimmune diseases. This could provide minor evidence to suggest that IGM is an autoimmune granulomatous disease with a local course.

Eosinophilic granulomatosis with polyangiitis - Advances in pathogenesis, diagnosis, and treatment

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare disease characterized by eosinophil-rich granulomatous inflammation and necrotizing vasculitis, pre-dominantly affecting small-to-medium-sized vessels. It is categorized as a primary antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) but also shares features of hypereosinophilic syndrome (HES); therefore, both vessel inflammation and eosinophilic infiltration are suggested to cause organ damage. This dual nature of the disease causes variable clinical presentation. As a result, careful differentiation from mimicking conditions is needed, especially from HES, given the overlapping clinical, radiologic, and histologic features, and biomarker profile. EGPA also remains a diagnostic challenge, in part because of asthma, which may pre-dominate for years, and often requires chronic corticosteroids (CS), which can mask other disease features. The pathogenesis is still not fully understood, however, the interaction between eosinophils and lymphocytes B and T seems to play an important role. Furthermore, the role of ANCA is not clear, and only up to 40% of patients are ANCA-positive. Moreover, two ANCA-dependent clinically and genetically distinct subgroups have been identified. However, a gold standard test for establishing a diagnosis is not available. In practice, the disease is mainly diagnosed based on the clinical symptoms and results of non-invasive tests. The unmet needs include uniform diagnostic criteria and biomarkers to help distinguish EGPA from HESs. Despite its rarity, notable progress has been made in understanding the disease and in its management. A better understanding of the pathophysiology has provided new insights into the pathogenesis and therapeutic targets, which are reflected in novel biological agents. However, there remains an ongoing reliance on corticosteroid therapy. Therefore, there is a significant need for more effective and better-tolerated steroid-sparing treatment schemes.

New Insights into Pathogenesis and Treatment of ANCA-Associated Vasculitis: Autoantibodies and Beyond

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a group of rare systemic diseases affecting small-caliber vessels. The damage caused by AAV mainly involves the lung and kidneys. AAV includes three different types: granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Although the different phenotypic forms of AAV share common features, recent studies have shown that there are significant differences in terms of pathogenetic mechanisms involving both the adaptive and innate immune systems. Advances in our understanding of pathogenesis have enabled the development of immuno-targeted therapies. This review illustrates the characteristics of the various forms of AAV and the new therapies available for this disease that can have lethal consequences if left untreated.

Examination of nailfold videocapillaroscopy findings in ANCA-associated vasculitis

OBJECTIVE

The objective of this study was to evaluate nailfold videocapillaroscopy (NVC) as a useful tool for assessing the disease activity of ANCA-associated vasculitis (AAV).

METHODS

This study enrolled 51 patients with AAV and 21 healthy controls. We scored NVC findings semiquantitatively, and compared them between AAV patients and controls. We examined the association of NVC findings with disease activity indicators, histopathological findings of skin biopsies, and high-resolution CT (HRCT) scores in AAV. Additionally, we repeatedly rated the NVC findings 3 months after immunosuppressive therapy.

RESULTS

Of the 51 enrolled patients, 36 (70.6%) showed a microangiopathy pattern and 4 (7.8%) showed a scleroderma pattern in AAV. The scores for microhaemorrhage, capillary loss, neoangiogenesis, and tortuosity were significantly higher in the AAV group than in the control group. NVC abnormalities correlated with the severity of skin, lung and kidney involvement. The scores of giant capillaries significantly correlated with the total BVAS and the chest BVAS; the scores of capillary loss correlated with the chest BVAS and the renal BVAS. The scores of microhaemorrhage significantly correlated with perivascular inflammatory cell infiltrations in the upper dermis of the purpura and tended to correlate with the total ground-glass opacity and consolidation scores on HRCT. In addition, capillary loss scores had a significant positive correlation with serum creatinine levels. Additionally, the microhaemorrhage scores were significantly reduced after 3 months of immunosuppressive therapy.

CONCLUSION

In AAV patients, NVC abnormalities are significantly associated with disease severity. This result suggests that NVC is a useful tool for assessing the disease activity and treatment response in AAV.

Successful use of mepolizumab for severe hypereosinophilic vasculitis with c-ANCA positivity in a previously healthy 7-year-old boy

An unusual case of a pediatric patient with severe eosinophilic vasculitis causing digital ischemia is reported. The patient responded well to the anti-IL-5 agent mepolizumab, lending support for use of mepolizumab in pediatric patients with hypereosinophilic syndromes.

Necrotizing Scleritis as a Manifestation of Eosinophilic Granulomatosis With Polyangiitis: A Case Report

Eosinophilic granulomatosis with polyangiitis (EGPA) is an ANCA-associated vasculitis characterized by the development of necrotizing granulomas rich in eosinophils and vasculitis of small and medium vessels, with compromise of the respiratory tract, peripheral nervous system, and least frequent ocular involvement. We report the case of a 54-year-old Caucasian man with a history of EGPA who presented ocular pain, red eye, vision loss, and evidence of scleral slimming compatible with necrotizing scleritis. The patient was treated with systemic steroids and cyclophosphamide, which reduced the ocular pain but did not improve visual acuity, needing surgical treatment of the scleral coverage defect. While necrotizing scleritis is an unusual manifestation of EGPA, it should be part of the differential diagnosis in patients with red eye or ocular pain as an accurate diagnosis and prompt treatment could reduce local complications.

Ischaemic stroke as the first presentation of antineutrophilic cytoplasmic autoantibody-associated vasculitis

The diagnosis of antineutrophil cytoplasmic autoantibody-associated vasculitis in first-episode strokes is particularly challenging, especially in patients lacking features of systemic vasculitis. We present the case of a 71-year-old woman with positive myeloperoxidase antineutrophil cytoplasmic antibodies and negative proteinase 3 autoantibodies. The patient presented with 1 week history of pyramidal weakness in both upper and lower limbs, hyperreflexia, and clonus. Magnetic resonance imaging of the brain demonstrated widespread bihemispheric cortical and deep white matter acute infarcts, which are consistent with features of stroke secondary to vasculitis. Myeloperoxidase antineutrophilic cytoplasmic autoantibody-positive vasculitis diseases are more commonly associated with renal, pulmonary, and cutaneous manifestations; however, in our patient, the central nervous system features predominated. This case highlights the challenges of diagnosing primary central nervous system vasculitis, in this case, an atypical myeloperoxidase antineutrophilic cytoplasmic autoantibody-positive disease without the classical disease course and clinical signs.

Benralizumab in the management of rare primary eosinophilic lung diseases

Background: Eosinophils have a double-edged role in the human body, being essential in important physiologic functions but whose presence is conspicuous in a variety of diseases characterized by a T2 inflammation phenotype. Eosinophils are exquisitely sensitive to corticosteroids, and the latter have, until recently, represented the cornerstone of treatment of eosinophilic diseases. However, most patients remain dependent on oral corticosteroids, with a notable adverse effect burden and experience a chronic relapsing disease that leads to high morbidity and mortality. Treatment prospects have changed with the advent of biologic drugs that target the eosinotropic cytokine interleukin (IL) 5 or its receptor. The success of the latter drugs in severe eosinophilic asthma has paved the way for their use in other, rarer, eosinophilic lung diseases. Recently, mepolizumab, a humanized monoclonal antibody that works against IL-5, was approved for the add-on treatment of relapsing-remitting or refractory eosinophilic granulomatosis with polyangiitis (EGPA) in patients ages ≥ 6 years. Benralizumab, a humanized antibody that binds to the α portion of the IL-5 receptor, is also being tested for its efficacy in EGPA in two clinical trials, after a growing number of case reports and case series supported its use as a steroid-sparing agent in the treatment of EGPA. Methods: In this review, we summarized the scientific literature evaluating the efficacy of benralizumab treatment in patients afflicted with rare primary eosinophilic lung diseases. Results: The literature we found, largely case reports, reported that the use of benralizumab in EGPA, chronic eosinophilic pneumonia (CEP) and allergic bronchopulmonary aspergillosis (ABPA) often led to a depletion of eosinophils, less exacerbations and a decreased systemic corticosteroid burden. No adverse effects were reported. Conclusion: Benralizumab has a prospective role in the treatment of rare eosinophilic lung diseases, which needs to be further elucidated in randomized controlled trials.

Eosinophilic Granulomatosis with Polyangiitis

This review aims to describe the epidemiology, pathogenesis, clinical manifestations, diagnosis, treatment, and prognosis of eosinophilic granulomatosis with polyangiitis (EGPA). Eosinophilic granulomatosis with polyangiitis is a small to medium vessel necrotizing vasculitis, typically classified with granulomatosis with polyangiitis (GPA) and microscopic polyangitis (MPA) as antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). However, less than 50% of patients with EGPA have a positive ANCA test. Among all the vasculitides, asthma and eosinophilia are unique features of EGPA. Eosinophilic granulomatosis with polyangiitis is very rare and the diagnosis may be missed as the disease evolves over time. Polyneuropathies are common and may be severe, requiring aggressive immunosuppressive therapy. Heart involvement is the most common cause of death in EGPA. Biopsy of involved tissue supports a clinically suspected diagnosis but is not always feasible. Treatment of EGPA is primarily dictated by the severity of disease and prognostic factors. More severe disease frequently requires the use of aggressive therapy such as cyclophosphamide. Once treatment is initiated, patients can achieve good control of symptoms; unfortunately, disease relapses are common and prolonged treatment with corticosteroids is often necessary for asthma management. A better understanding of the disease heterogeneity is needed for the development of better therapies.

Eosinophilic Gastroenteritis in the Small Intestine Mimicking Eosinophilic Granulomatosis With Polyangiitis in a Young Male Patient

Eosinophilic gastroenteritis (EGE) is a disease involving the gastrointestinal tract that involves the invasion of eosinophils into the lumen of the tract. Invasion of eosinophils in the tract causes edema and inflammation of the wall, resulting in acute or chronic diarrhea and abdominal pain. EGE can cause chronic inflammation in the small intestine, thereby mimicking chronic vasculitis. We report the case of a 24-year-old male patient with the chief complaint of acute progressive abdominal pain. Endoscopic findings of the small intestine were chronic and similar to those of polyangiitis (eosinophilic granulomatosis with polyangiitis). This case shows the presence of various clinical courses of EGE and the discrepancy between the symptoms and endoscopic appearance of vasculitis. Physicians should focus not only on acute symptoms but also on chronic phases of the disease to prevent disease progression and modify patients’ help-seeking behaviors according to their symptoms.

Neutrophils in ANCA-associated vasculitis: Mechanisms and implications for management

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of systemic autoimmune diseases, which is typified by inflammatory necrosis predominantly affecting the small vessels and often accompanied by positive ANCA. Clinically, AAV primarily includes microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA), and eosinophilic granulomatosis with polyangiitis (EGPA). It has been found that in AAV pathogenesis, both innate and adaptive immunity are related to neutrophil function mutually. Many proteins, such as myeloperoxidase (MPO) and proteinase 3 (PR3), in neutrophil cytoplasm lead to the production of proteins such as MPO-ANCA and PR3-ANCA by activating adaptive immunity. In addition, through the process of neutrophil extracellular trap (NET) formation, activation of an alternative complement pathway and the respiratory burst can stimulate the neutrophils close to vascular endothelial cells and will participate the vessel inflammation. This review aims to reveal the potential mechanisms regulating the association between the neutrophils and various types of AAVs and to emphasize the results of recent findings on these interactions. Moreover, multiple underlying signaling pathways involved in the regulation of neutrophils during AAV processes have also been discussed. The ultimate goal of this review is to identify novel biomarkers and therapeutic targets for AAV management in the future.

The Role of T Helper Type 2 (Th2) Cytokines in the Pathogenesis of Eosinophilic Granulomatosis with Polyangiitis (eGPA): an Illustrative Case and Discussion

Purposeof Review

The pathogenesis of eosinophilic granulomatosis with polyangiitis (eGPA) is driven largely by CD4 + type 2 helper T cells (Th2), B cells, and eosinophils. Interleukin (IL)-4 and IL-13 are critical cytokines in Th2 cell–mediated inflammation; however, inhibition of IL-4 and IL-13 does not reduce serum eosinophil counts and has even been associated with hypereosinophilia. This review explores the role of IL-4, IL-5, and IL-13 in Th2-mediated inflammation to consider the potential clinical consequences of inhibiting these individual cytokines in eGPA.

Recent Findings

Treatments for eosinophilic granulomatosis with polyangiitis (eGPA) are rapidly evolving through using biologic therapies to modulate the Th2 inflammatory response via eosinophil inhibition. While IL-4, IL-5, IL-13, and IL-25 can all affect eosinophils, only IL-5 inhibition has demonstrated therapeutic benefit to-date. In this review, we report a clinical vignette of a patient with adult-onset asthma who developed severe manifestations of eGPA after switching from mepolizumab (an IL-5 inhibitor) to dupilumab (an inhibitor of IL-4 and IL-13).

Summary

By understanding the role of IL-4, IL-5, and IL-13 in Th2-mediated vasculitis, we can start to understand how eGPA might respond differently to focused cytokine inhibition.

The Diagnostic Challenge of Eosinophilic Granulomatosis With Polyangiitis Presenting as Acute Eosinophilic Myocarditis: Case Report and Literature Review

Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic vasculitis involving small-to-medium-sized vessels characterized by asthma, vasculitis, and peripheral eosinophilia. EGPA-associated eosinophilic myocarditis (EM) occurs rarely, yet can be fatal if left untreated. Moreover, the accurate diagnosis of EGPA-associated EM without vasculitis is exceptionally difficult because of the overlapping features with EM of other causes. We report a case of probable EGPA with subclinical neurological involvement that presented with acute EM. The constellation of peripheral eosinophilia, left ventricular dysfunction, and normal epicardial coronary arteries raised suspicion of acute EM, which was confirmed by cardiac magnetic resonance (CMR) investigation and endomyocardial biopsy (EMB). Prompt systemic administration of corticosteroids completely restored and normalized myocardial structure and function. Although the patient's history suggested the presumed hypersensitivity myocarditis, EMB revealed EM without vasculitis, not hypersensitivity, leading to a tentative diagnosis of idiopathic hypereosinophilic syndrome. Interestingly, the characteristic findings of vasculitis on CMR imaging strongly suggested EGPA-associated EM. Although the patient had no clinical neurological manifestations, a nerve conduction study confirmed mononeuritis multiplex, leading to the final diagnosis of probable EGPA. Therefore, this case highlights the diagnostic challenge associated with EGPA and the diagnostic synergy of CMR and EMB for an exploratory diagnosis of EGPA-associated EM.

Serum Proteomic Analysis Identifies SAA1, FGA, SAP, and CETP as New Biomarkers for Eosinophilic Granulomatosis With Polyangiitis

Background

Eosinophilic granulomatosis with polyangiitis (EGPA) is characterized by asthma-like attacks in its early stage, which is easily misdiagnosed as severe asthma. Therefore, new biomarkers for the early diagnosis of EGPA are needed, especially for differentiating the diagnosis of asthma.

Objectives

To identify serum biomarkers that can be used for early diagnosis of EGPA and to distinguish EGPA from severe asthma.

Method

Data-independent acquisition (DIA) analysis was performed to identify 45 healthy controls (HC), severe asthma (S-A), and EGPA patients in a cohort to screen biomarkers for early diagnosis of EGPA and to differentiate asthma diagnosis. Subsequently, parallel reaction monitoring (PRM) analysis was applied to a validation cohort of 71 HC, S-A, and EGPA patients.

Result

Four candidate biomarkers were identified from DIA and PRM analysis-i.e., serum amyloid A1 (SAA1), fibrinogen-α (FGA), and serum amyloid P component (SAP)-and were upregulated in the EGPA group, while cholesteryl ester transfer protein (CETP) was downregulated in the EGPA group compared with the S-A group. Receiver operating characteristics analysis shows that, as biomarkers for early diagnosis of EGPA, the combination of SAA1, FGA, and SAP has an area under the curve (AUC) of 0.947, a sensitivity of 82.35%, and a specificity of 100%. The combination of SAA1, FGA, SAP, and CETP as biomarkers for differential diagnosis of asthma had an AUC of 0.921, a sensitivity of 78.13%, and a specificity of 100%, which were all larger than single markers. Moreover, SAA1, FGA, and SAP were positively and CETP was negatively correlated with eosinophil count.

Conclusion

DIA-PRM combined analysis screened and validated four previously unexplored but potentially useful biomarkers for early diagnosis of EGPA and differential diagnosis of asthma.

Eosinophilic Granulomatosis With Polyangiitis Presenting With Oral Granuloma as the Initial Symptom: A Case Report

Antineutrophil cytoplasmic antibody associated vasculitis includes granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis (EGPA), and microscopic polyangiitis. While EGPA has no specific symptoms, it usually presents as necrotizing vasculitis, eosinophil infiltration of the tissues and organs, and extravascular granuloma formation. Here, we report a patient who had a rare initial presentation of oral granuloma and had been previously misdiagnosed several times at other hospitals. He was finally diagnosed with EGPA and recovered after methylprednisolone and cyclophosphamide treatment. The disease EGPA can present with a rare initial presentation of oral granuloma, methylprednisolone, and cyclophosphamide can be a suitable choice of treatment.

From Churg-Strauss Syndrome to Eosinophilic Granulomatosis With Polyangiitis: A Historical Review of Nomenclature and Diagnostic Criteria

ABSTRACT

Eosinophilic granulomatosis with polyangiitis (EGPA) is rare vasculitis syndrome that involves the skin and other organ systems manifesting as asthma, eosinophilia, and pulmonary infiltrates. The understanding of EGPA, previously known as Churg-Strauss Syndrome, has continued to evolve from its earliest documentation in the literature in 1951. Herein, we review key historical advances in the diagnosis, classification, and nomenclature of EGPA that have shaped our understanding of this protean disorder over time.

Severe Asthma Where Eosinophilic Granulomatosis with Polyangiitis Became Apparent after the Discontinuation of Dupilumab

The use of biologic agents has enabled control of severe asthma, but there is a risk that eosinophilic granulomatosis with polyangiitis (EGPA) may be masked in some cases. We herein report a 71-year-old man who was administered dupilumab for 2 years to stabilize his asthma symptoms. A few months after discontinuation of dupilumab administration, an increase in the eosinophil count in peripheral blood, leg pain, and a rash appeared. Based on pathology, he was diagnosed with EGPA. EGPA in this case was considered to have become apparent due to the discontinuation of dupilumab administration.

A case report of myocardial infarction with non-obstructive coronary arteries as the initial presentation of eosinophilic granulomatosis with polyangiitis

Background

Eosinophilic granulomatosis with polyangiitis (EGPA) is a multisystem disorder commonly affecting the lung and skin, with cardiovascular involvement found in up to 60% of patients. We present a case of myocardial infarction with non-obstructive coronary arteries (MINOCA) as the initial presentation of EGPA.

Case summary

A 52-year-old female with past medical history of asthma, recurrent sinusitis, and peripheral neuropathy presented to our hospital with chest pain, rash, acute vision loss, elevated troponin, and peripheral eosinophilia. Electrocardiogram showed no ischaemic changes and coronary angiography displayed normal coronary anatomy. On a subsequent visit, cardiac magnetic resonance (CMR) showed predominant focal anteroseptal and inferoseptal akinesis with focal sub-endocardial delayed enhancement, indicative of a myocardial infarction involving the septal branches of the left anterior descending artery. Due to the focal findings on CMR, peripheral eosinophilia, and rash, the patient was evaluated for EGPA. Rheumatologic workup and skin biopsy were suggestive of small vessel vasculitis. The patient was diagnosed with multi-organ EGPA, involving the coronaries, which was ultimately thought to be the aetiology of her MINOCA. Following steroid and monoclonal antibody therapy, the patient experienced notable improvement in her cardiac function at follow-up appointments.

Discussion

This is a unique case MINOCA as the initial presentation of EGPA. Considering the heterogeneous disease presentation of those diagnosed with MINOCA, utilization of CMR is essential to guide diagnosis and management of such patients.

[ANCA-associated small-vessel vasculitides]

ANCA-associated vasculitides refer to systemic small-vessel vasculitides. The paper shows the role of antineutrophil cytoplasmic antibodies in the development of immune inflammation of blood vessels and tissues. It considers the pathogenesis of granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis and presents the clinical and morphological manifestations of the diseases.

Antineutrophil Cytoplasmic Antibody-Associated Vasculitis: Toward an Individualized Approach

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), characterized by the presence of autoantibodies to neutrophil cytoplasmic antigens, proteinase 3 (PR3), and myeloperoxidase (MPO), typically involves small blood vessels of the respiratory tract and kidneys. It includes distinct clinical syndromes: microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA), and eosinophilic GPA. GPA is commonly associated with PR3-ANCA, while MPA is associated with MPO-ANCA. AAVs have a complex pathogenesis, influenced by genetics and environmental factors. There is evidence for a loss of tolerance to neutrophil proteins, which leads to ANCA-mediated neutrophil activation and injury, with effector T cells and activation of the alternative pathway of the complement also involved. Advances in immunosuppressive treatment have drastically reduced mortality of AAV in the past decades, opting for a more individualized approach. Careful assessment of ANCA specificity, disease activity, organ damage, and quality of life allows for a tailored immunosuppressive therapy. Contemporary AAV treatment is characterized by regimens that minimize the cumulative exposure to glucocorticoids and cyclophosphamide, and novel approaches including complement blockage and immunosuppressant combinations might be the standard of care in the future. In this review, we examine the pathogenesis, clinical approach, and evidence-based treatment options for the management of AAV patients.

Cardiac Involvement in Eosinophilic Granulomatosis with Polyangiitis (Churg-Strauss Disease): The role of cardiovascular magnetic resonance

Eosinophilic granulomatosis with polyangiitis (EGPA), previously known as Churg-Strauss disease, is a rare vasculitis that affects small- to medium-sized vessels and has a propensity to involve the heart. Patients with cardiac involvement have a poor prognosis and usually require immunosuppressive treatment along with corticosteroids. Cardiovascular magnetic resonance (CMR) is a non-invasive diagnostic tool for detecting cardiac involvement and guiding the management plan. We report a 39-year-old male patient with a known history of bronchial asthma who was referred to the chest clinic at a tertiary hospital in 2019 for further assessment of persistent lung parenchymal changes on chest computed tomography. Given the clinical context of the patient and the radiological findings, EGPA was suspected and confirmed with a lung biopsy. CMR was performed for further assessment, which confirmed cardiac involvement. The patient was started on prednisolone and azathioprine and showed significant radiological and clinical improvement.

Plasma Exchange in ANCA-Associated Vasculitis: A Narrative Review

Therapeutic plasma exchange (TPE) is an adjunctive intervention to immunosuppression for the treatment of severe renal involvement or lung hemorrhage in patients with ANCA-associated vasculitis (AAV). Patients with AAV have an increased risk for progression to end-stage kidney disease (ESKD) or death despite advances in immunosuppressive therapy. The potential pathogenicity of ANCA makes TPE a reasonable treatment approach for the life-threatening complications of AAV. The efficacy of intensive TPE in rapidly progressive glomerulonephritis was originally described in small studies almost four decades ago. Further randomized trials examined the addition of TPE to standard of care, exhibiting mixed results in both patient and renal survival. The largest clinical trial to date, PEXIVAS, failed to demonstrate a clear benefit for TPE in severe AAV. In light of new evidence, the role of TPE remains controversial across the vasculitis medical community. The purpose of this review is to summarize the clinical indications and the current available data for the use of TPE in patients with severe AAV.

B-Cell-Depleting Therapy Improves Myocarditis in Seronegative Eosinophilic Granulomatosis with Polyangiitis

Cardiac involvement is a major mortality cause in eosinophilic granulomatosis with polyangiitis (EGPA), requiring novel therapeutics to spare the use of cyclophosphamide with known cardiotoxicity. Despite the observed efficacy of B-cell-depleting therapy in myocarditis of seropositive microscopic polyangiitis, it remains to be elucidated in seronegative EGPA. A retrospective study was performed in 21 hospitalized active patients aged 20 to 70 years with five-factor score 1 or 2, eosinophil counts 10,034 ± 6641/μL and vasculitis scores 27 ± 6. Overt myocarditis was identified in 10 cases, at disease onset in 6 and relapse in 4, with endomyocarditis in 4 and myopericarditis in 4. Five seronegative and one seropositive patient received rituximab with an induction regimen 375 mg/m² weekly × 4 for refractory or relapse disease, and the same regimen for annual maintenance therapy. All cases had lower eosinophil counts, improved cardiac dysfunction and clinical remission with a relapse-free follow-up, 48 ± 15 months after the induction treatment. One seronegative endomyocarditis patient had eosinophilia and disease relapse with asthma attack and worsening cardiac insufficiency 24 months after induction, achieving clinical remission under anti-IL-5 therapy. Our findings suggest the suppression of IL-5-mediated eosinophilia as an action mechanism of B-cell-depleting therapy in seronegative EGPA myocarditis.

Eosinophils in Health and Disease: A State-of-the-Art Review

Eosinophils play a homeostatic role in the body's immune responses. These cells are involved in combating some parasitic, bacterial, and viral infections and certain cancers and have pathologic roles in diseases including asthma, chronic rhinosinusitis with nasal polyps, eosinophilic gastrointestinal disorders, and hypereosinophilic syndromes. Treatment of eosinophilic diseases has traditionally been through nonspecific eosinophil attenuation by use of glucocorticoids. However, several novel biologic therapies targeting eosinophil maturation factors, such as interleukin (IL)-5 and the IL-5 receptor or IL-4/IL-13, have recently been approved for clinical use. Despite the success of biologic therapies, some patients with eosinophilic inflammatory disease may not achieve adequate symptom control, underlining the need to further investigate the contribution of patient characteristics, such as comorbidities and other processes, in driving ongoing disease activity. New research has shown that eosinophils are also involved in several homeostatic processes, including metabolism, tissue remodeling and development, neuronal regulation, epithelial and microbiome regulation, and immunoregulation, indicating that these cells may play a crucial role in metabolic regulation and organ function in healthy humans. Consequently, further investigation is needed into the homeostatic roles of eosinophils and eosinophil-mediated processes across different tissues and their varied microenvironments. Such work may provide important insights into the role of eosinophils not only under disease conditions but also in health. This narrative review synthesizes relevant publications retrieved from PubMed informed by author expertise to provide new insights into the diverse roles of eosinophils in health and disease, with particular emphasis on the implications for current and future development of eosinophil-targeted therapies.

A case of eosinophilic granulomatosis with polyangiitis after prolonged intervals of an anti-interleukin-6 receptor antibody for rheumatoid arthritis

An 83-year-old woman with a history of asthma complained of left abdominal pain and was admitted to our hospital. She was treated with tocilizumab, an anti-interleukin (IL)-6 receptor antibody, with a prolonged interval for rheumatoid arthritis (RA). Laboratory tests revealed a remarkable increase in eosinophil count and inflammatory markers with negative antineutrophil cytoplasmic antibodies. Echocardiography revealed pericardial fluid retention, and contrast-enhanced computed tomography revealed the thickening of the gastric antrum wall. Upper gastrointestinal endoscopy and biopsy revealed eosinophilic infiltration into the gastric mucosal epithelium. She was diagnosed with eosinophilic granulomatosis with polyangiitis (EGPA) with pericarditis and eosinophilic gastroenteritis. High-dose glucocorticoids with intermittent intravenous cyclophosphamide (IVCY) were initiated, resulting in remission. As IL-6 is involved in the pathogenesis of allergic diseases such as asthma, our case can provide insights into the pathogenic role of IL-6 in EGPA as the development of EGPA in our case may have been triggered by IL-6 signals enhanced with tocilizumab interval prolongation.

Rituximab and Mepolizumab Combination Therapy for Glucocorticoid-Resistant Myocarditis Related to Eosinophilic Granulomatosis With Polyangiitis

Eosinophilic granulomatosis with polyangiitis (EGPA), which belongs to the anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides, is characterized by eosinophil-rich granulomatous inflammation and small to medium-sized vessel vasculitis associated with bronchial asthma and eosinophilia. It sometimes causes severe organ damage, of which myocardial damage is one of the most important for determining the prognosis. A case of EGPA-associated myocarditis that was refractory to glucocorticoid therapy and responded successfully to rituximab (RTX) and mepolizumab (MPZ) combination therapy is presented. A 46-year-old woman was diagnosed with EGPA-associated myocarditis due to pre-existing asthma, eosinophilia, mononeuritis multiplex, and eosinophilic myocarditis by myocardial biopsy. Transthoracic echocardiography showed thickening of the cardiac wall, pericardial effusion, and left ventricular hypokinesis. Although the myocarditis was refractory to methylprednisolone pulse therapy followed by oral high-dose prednisolone, the disease activity reached remission with the successful tapering of glucocorticoid after initiation of the RTX and MPZ combination therapy. Combination therapy with RTX and MPZ can be a good treatment option for EGPA-associated myocarditis for which it is difficult to give intravenous cyclophosphamide due to cardiac dysfunction.

A Progressive Case of Eosinophilic Myocarditis Due to Eosinophilic Granulomatosis With Polyangiitis in a Caucasian Male

Vasculitis is an inflammatory process involving blood vessels of various sizes, including the small vessels in the kidneys to the large vessels, such as the aorta. This inflammatory condition is usually autoimmune in nature and is associated with involvement of many locations, such as the sinuses, lungs, kidneys, and even the heart. Specifically, eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic vasculitis that may initially hide as asthma, allergic rhinitis, and/or sinusitis. However, it is known to become a lethal disease once progressed to include cardiovascular manifestations. It is important to remember EGPA as a differential for any patient with a history of asthma, allergic rhinitis, and/or sinusitis who also presents with cardiovascular complaints and eosinophilia. Treatment recommendations focus on immunosuppression in such cases. In this article, we discuss the case of a 62-year-old male, with a known history of asthma, who presented to the emergency department with concern for his chest pain and right-sided weakness. He was later diagnosed with EGPA with eosinophilic myocarditis. Diagnosis and treatment are described.