Prevalence and clinical significance of antineutrophil cytoplasmic antibodies in Churg-Strauss syndrome

Eosinophilic granulomatosis with polyangiitis and its association with montelukast: a case-based review

The association between the use of certain medications (including sulfonamides, hydralazine, and procainamide) and the occurrence of drug-induced lupus or hepatitis is well established. More recently, cases of immune-related adverse events ranging from inflammatory polyarthritis to necrotizing myositis in patients taking checkpoint inhibitors have been reported. However, data linking drugs to systemic vasculitis are scarce and at times debatable. Propylthiouracil, hydralazine, and minocycline have been associated with rare cases of ANCA-associated syndromes, including life-threatening pulmonary-renal syndromes and systemic polyarteritis nodosa-like diseases. Eosinophilic granulomatosis with polyangiitis (EGPA) has been reported in patients taking leukotriene inhibitors. Since the link between the use of leukotriene inhibitors and occurrence of EGPA remains highly controversial, we performed a literature review for cases of EGPA in patients taking montelukast without prior history of oral corticosteroid use. We found 24 cases, along with our own two cases described, making 26 cases in total. The mean age was 43 and a majority (18/26) were female. In majority of cases EGPA-like disease never relapsed after they were taken off leukotriene inhibitors suggesting a clear causal relationship between the use of these drugs and occurrence of eosinophil-rich systemic EGPA.

When inflammation is not just inflammation-A review of systemic diseases of the nose and sinuses part 2: Granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis

BACKGROUND

Chronic rhinosinusitis is a very common condition. Granulomatosis with polyangiitis (GPA) and eosinophilic granulomatosis with polyangiitis (eGPA) are systemic diseases which can contribute to the development of chronic rhinosinusitis in select patients.

OBJECTIVE

Characterize the presenting features, diagnostic criteria, workup, and management of granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis as they are encountered in otolaryngology clinics.

METHODS

Full length manuscripts published 2000 or later were reviewed. A separate search was conducted for each disease. Pertinent clinical features related to sinonasal manifestations of GPA and eGPA were collected and reported in this review.

RESULTS

467 references were discovered during literature review process. In total, 42 references for GPA and 35 references for eGPA were included in this review.

CONCLUSION

GPA and eGPA are vasculitis syndromes which commonly present in the context of multisystem disease. For GPA, pulmonary and renal disease are common; for eGPA a history of asthma is nearly ubiquitous. Sinonasal disease is a very common feature for both disease processes and may precede the development of systemic symptoms in many patients. Clinical work up and diagnosis is complex and generally requires multidisciplinary care. Treatment primarily consists of immunosuppressive agents, and a number of steroids, steroid sparing agents, and biologics have been shown to be effective. The role of sinus surgery includes tissue biopsy for diagnosis, functional surgery for symptom management in select cases, and reconstruction of cosmetic and functional defects.

Clinical Characteristics of EGPA Patients in Comparison to GPA Subgroup with Increased Blood Eosinophilia from POLVAS Registry

Objective

To characterize the eosinophilic granulomatosis with polyangiitis (EGPA) population from the POLVAS registry depending on ANCA status and diagnosis onset, including their comparison with the granulomatosis with polyangiitis (GPA) subset with elevated blood eosinophilia (min. 400/μl) (GPA HE) to develop a differentiating strategy.

Methods

A retrospective analysis of the POLVAS registry.

Results

The EGPA group comprised 111 patients. The ANCA-positive subset (n = 45 [40.54%]) did not differ from the ANCA-negative one in clinics. Nevertheless, cardiovascular manifestations were more common in ANCA-negative patients than in those with anti-myeloperoxidase (MPO) antibodies (46.97% vs. 26.92%, p = 0.045). Patients diagnosed before 2012 (n = 70 [63.06%]) were younger (median 41 vs. 49 years, p  < 0.01), had higher blood eosinophilia at diagnosis (median 4,946 vs. 3,200/μl, p  < 0.01), and more often ear/nose/throat (ENT) and cardiovascular involvement. GPA HE comprised 42 (13.00%) out of 323 GPA cases with reported blood eosinophil count. Both GPA subsets had a lower prevalence of respiratory, cardiovascular, and neurologic manifestations but more often renal and ocular involvement than EGPA. EGPA also had cutaneous and gastrointestinal signs more often than GPA with normal blood eosinophilia (GPA NE) but not GPA HE. The model differentiating EGPA from GPA HE, using ANCA status and clinical manifestations, had an AUC of 0.92, sensitivity of 96%, and specificity of 95%.

Conclusion

Cardiovascular symptoms were more prevalent in the ANCA-negative subset than in the MPO-ANCA-positive one. Since EGPA and GPE HE share similarities in clinics, diagnostic misleading may result in an inappropriate therapeutic approach. Further studies are needed to optimize their differentiation and tailored therapy, including biologics.

Azathioprine vs methotrexate in eosinophilic granulomatosis with polyangiitis: a monocentric retrospective study

OBJECTIVES

To analyse the effectiveness, safety and steroid-sparing effect of AZA and MTX as induction of remission and maintenance treatment in eosinophilic granulomatosis with polyangiitis.

METHODS

We retrospectively collected data from 57 patients divided into four groups according to treatment: MTX/AZA as first-line agents (MTX1/AZA1) in non-severe disease or as second-line maintenance therapy (MTX2/AZA2) in severe disease previously treated with CYC/rituximab. During the first 5 years of treatment with AZA/MTX we compared the groups according to: remission rate [defined as R1: BVAS = 0; R2: BVAS = 0 with prednisone ≤5 mg/day; R3 (MIRRA definition): BVAS = 0 with prednisone ≤3.75 mg/day], persistence on therapy, cumulative glucocorticoid (GC) dose, relapse and adverse events (AEs).

RESULTS

There were no significant differences in remission rates (R1) in each group (63% in MTX1 vs 75% in AZA1, P = 0.53; 91% in MTX2 vs 71% in AZA2, P = 0.23). MTX1 allowed R2 more frequently in the first 6 months compared with AZA1 (54% vs 12%, P = 0.04); no patients receiving AZA1 achieved R3 up to the first 18 months (vs 35% in MTX1, P = 0.07). The cumulative GC dose was lower for MTX2 vs AZA2 (6 g vs 10.7 g at 5 years, P = 0.03). MTX caused more AEs compared with AZA (66% vs 30%, P = 0.004), without affecting the suspension rate. No differences emerged in time-to-first relapse, although fewer patients treated with AZA2 had asthma/ENT relapses (23% vs 64%, P = 0.04).

CONCLUSION

A significant proportion of patients achieved remission with both MTX and AZA. MTX1 had an earlier remission on a lower GC dose but MTX2 had a better steroid-sparing effect.

Pulmonary pathology in vasculitis

Pulmonary involvement is frequent in vasculitis, particularly in ANCA-associated small vessel vasculitis. Laboratory and radiological data alone are often sufficient to confirm the clinical hypothesis, but sometimes the pathologist plays a crucial role in the differential diagnosis and the patient's management. In this review, the pathologic features of pulmonary vasculitis and the pathologist's role in this field are illustrated.

Cutaneous vasculitis: insights into pathogenesis and histopathological features

The mechanisms underlying the onset and progression of vasculitis remain poorly understood. This condition is characterized by damage to the vascular wall, recruitment of inflammatory cells, and subsequent structural remodeling, which are hallmarks of vasculitis. The histopathological classification of vasculitis relies on the size of the affected vessel and the predominant type of inflammatory cell involved - neutrophils in acute cases, lymphocytes in chronic conditions, and histiocytes in granulomatous forms. Pathological changes progress in every context, and a single vasculitic pattern can be associated with various systemic conditions. Conversely, a single causative agent may lead to multiple distinct clinical and pathological manifestations of vasculitis. Moreover, many cases of vasculitis have no identifiable cause. A foundational understanding of the normal structure of the cutaneous vascular network is crucial. Similarly, identifying the cellular and molecular participants and their roles in forming the "dermal microvascular unit" is propedeutical.

This review aims to elucidate the complex mechanisms involved in the initiation and progression of vasculitis, offering a comprehensive overview of its histopathological classification, underlying causes, and the significant role of the cutaneous vascular network and cellular dynamics. By integrating the latest insights from studies on NETosis and the implications of lymphocytic infiltration in autoimmune diseases, we seek to bridge gaps in current knowledge and highlight areas for future research. Our discussion extends to the clinical implications of vasculitis, emphasizing the importance of identifying etiological agents and understanding the diverse histopathological manifestations to improve diagnostic accuracy and treatment outcomes.

Mepolizumab and benralizumab in patients with severe asthma and a history of eosinophilic granulomatosis with polyangiitis

Introduction

Asthma associated with eosinophilic granulomatosis with polyangiitis (EGPA) is often severe and corticosteroid-dependent, leading to significant morbidity. Mepolizumab and benralizumab are humanized monoclonal antibodies targeting interleukin 5 (IL-5) and its receptor, respectively. They have been shown to be effective in steroid-sparing in patients with severe eosinophilic asthma.

Objective

Our aim was to evaluate the efficacy and safety of mepolizumab and benralizumab prescribed for severe asthma in patients with EGPA under "real-world" conditions.

Methods

This was a retrospective analysis of patients with EGPA and persistent asthma who received either mepolizumab 100 or 300 mg administered every 4 weeks, or benralizumab 30 mg administered every 4 weeks for the initial 3 injections and followed by an injection every 8 weeks thereafter, whilst combined with oral glucocorticoids. The follow-up every 6 ± 3 months included an assessment of clinical manifestations, pulmonary function tests and eosinophil cell count. The primary outcome was the proportion of patients at 12 months receiving a daily oral dose of prednisone or equivalent of 4 mg or less with a BVAS of 0.

Results

Twenty-six patients were included. After 12 months of treatment with mepolizumab or benralizumab, 32% of patients met the primary outcome and were receiving less than 4 mg of prednisone per day with a BVAS of 0. The median dose of prednisone was 10 mg per day at baseline, 9 mg at 6 months, and 5 mg at 12 months (p ≤ 0.01). At 12 months, 23% of patients were weaned off corticosteroids, while an increase or no change in dose was observed in 27% of patients. The median eosinophil count was significantly reduced from 365 cells/mm3 to 55 cells/mm3 at 6 months and 70 cells/mm3 at 12 months, respectively. No significant change was observed in FEV1. After 12 months of treatment, 14% of patients had had an average of 1 exacerbation of asthma, compared with 52% of patients before baseline. The tolerability profile was favorable.

Conclusion

In this real-world study in patients with severe asthma and a history of EGPA asthma, mepolizumab and benralizumab had a significant steroid-sparing effect and reduced asthma exacerbation, but no significant effect on lung function.

Treatment strategies for ANCA-associated vasculitides: from standard protocols to future horizons

INTRODUCTION

ANCA-associated vasculitides (AAV), classified into granulomatosis with polyangiitis, microscopic polyangiitis, and eosinophilic granulomatosis with polyangiitis represent a group of disorders characterized by necrotizing vasculitis of small vessels, endothelial injury and tissue damage. The outcomes and prognosis of AAV have undergone significant changes with the introduction of glucocorticoids (GCs) and other immunosuppressants (cyclophosphamide, azathioprine, methotrexate, and mycophenolate mofetil). The enhanced understanding of pathogenesis has subsequently led to the incorporation into clinical practice of drugs targeting specific therapeutic targets.

AREAS COVERED

After an extensive literature search of Pubmed, Medline, Embase of the most recent evidence, we provide an overview of available treatments, highlighting how newer drugs have integrated into standard protocols. Our review also explores potential new therapeutic targets, including B cell depletion and inhibition, T cell inhibition, complement inhibition, and IL-5 and IgE inhibition.

EXPERT OPINION

There is hope that the new treatment targets currently under study in AAV may enable a faster and more lasting clinical response, ensuring the reduction of possible side effects from therapies. Moreover, numerous aspects necessitate further exploration in the future, such as tailoring of GCs, integration of GCs-sparing agents, efficacy of combination therapy, optimal maintenance therapy, to reduce organ-damage and improve quality of life.

Incidence, Prevalence, and Mortality of Eosinophilic Granulomatosis With Polyangiitis in Korea: A Nationwide Population-Based Study

PURPOSE

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare form of vasculitis with multiorgan involvement. The incidence and prevalence of EGPA vary geographically and ethnically. This study investigated the incidence, prevalence, and mortality of EGPA in a nationwide population-based cohort in Korea.

METHODS

This retrospective cohort study used data from the National Health Insurance database that covers almost all Korean residents. EGPA was identified using relevant diagnostic codes from 2007 to 2018. Newly diagnosed EGPA cases since 2007 and patients who visited outpatient clinics for EGPA at least three times were included. Age- and sex-adjusted standardized incidence and prevalence rates were analyzed.

RESULTS

A total of 843 patients with EGPA were identified. The mean annual standardized incidence between 2007 and 2018 was 1.2 (per 1,000,000 individuals). The incidence of EGPA has increased from 1.1 (per 1,000,000 individuals) in 2007 to 1.6 (per 1,000,000 individuals) in 2017. The standardized prevalence of EGPA has increased from 1.1(per 1,000,000 individuals) in 2007 to 11.2 (per 1,000,000 individuals) in 2018. The incidence and prevalence of EGPA were higher in women than in men. The standardized mortality rate was 1.61 (95% confidence interval [CI], 1.34-1.93) in total population, 1.59 (95% CI, 1.23-2.02) in males, and 1.63 (95% CI, 1.22-2.13) in females.

CONCLUSIONS

The incidence of EGPA has increased over the past decade. Incidence and prevalence rates were higher in females than in males. The overall mortality rate associated with EGPA was higher than that in the general population.

Eosinophilic granulomatous with polyangiitis complicated by swelling of the oral cavity floor and cervical soft tissue as initial manifestation mimicking IgG4-related disease: A case report

Eosinophilic granulomatous polyangiitis is a systemic vasculitis associated with bronchial asthma and eosinophilic sinusitis. Here, we describe an unusual presentation of eosinophilic granulomatous polyangiitis that initially manifested as swelling of the oral cavity floor and cervical soft tissue. A 58 year-old Japanese man was diagnosed with bronchial asthma during childhood but did not receive regular medication. Prior to this presentation, he had a persistent cough for over 1 month, and a local physician diagnosed him with bronchial asthma. However, 6 months later, his cough worsened, and a blood test revealed elevated eosinophil levels. Immediately afterward, swelling of the floor of the oral cavity and cervical soft tissue developed. Cellulitis was suspected and antimicrobial treatment was initiated; however, the symptoms persisted and abdominal pain developed. An endoscopic examination revealed duodenitis and a duodenal ulcer. The patient was diagnosed with eosinophilic granulomatous polyangiitis based on three items of the 2022 American College of Rheumatology/European College of Rheumatology classification criteria: obstructive airway disease, blood eosinophil count ≥1 × 109 cells/L, and extravascular eosinophilic infiltration with a score of 10. Oral prednisolone (70 mg/day), intravenous cyclophosphamide (500 mg/m2), and subcutaneous mepolizumab (300 mg every 4 weeks) were administered. The patient's symptoms improved after these treatments, and the eosinophil count and inflammatory marker levels declined. When swelling of the oral cavity floor and cervical soft tissue following an increase in eosinophilia and allergic symptoms occurs, it is crucial to consider the likelihood of eosinophilic granulomatous polyangiitis and collaborate with otolaryngologists and dentists to ensure its prompt identification.

Evaluation of prognostic factors for patients with eosinophilic granulomatosis with polyangiitis recruited at the pneumonological centre and mainly ANCA negativity: A retrospective analysis of a single cohort in Poland

OBJECTIVES

The aim was to investigate the risk factors for relapse and death in patients with eosinophilic granulomatosis with polyangiitis (EGPA) recruited at the pneumonological centre and mainly antineutrophil cytoplasmic antibody negativity.

METHODS

We retrospectively recruited 86 patients. Relapse was defined as the recurrence or appearance of new organ symptoms. The study end-point included the final examination.

RESULTS

Relapses occurred in 34.9% of the patients, while 9.3% died. Immunosuppressive therapy (P = 0.042), prolonged low-dose corticosteroid treatments (mainly for asthma) (P = 0.006), and longer follow-up duration (P = 0.004) were associated with a higher relapse risk, while advanced EGPA severity (P = 0.0015) and activity (P = 0.044), older age of onset (P = 0.030), symptomatic cardiac involvement (P = 0.007), and postinflammatory cardiac fibrosis (P = 0.038) were associated with a higher risk of death. Sinusitis (P = 0.028) and prolonged low-dose corticosteroid treatments (P = 0.025) correlated with a better prognosis. Relapses did not have an impact on the mortality (P = 0.693).

CONCLUSIONS

Relapses in EGPA remain frequent, although they do not impact mortality. Cardiac involvement is common, but clinically symptomatic cardiomyopathy is associated with a higher risk of death. Asthma requiring chronic corticosteroid treatments is associated with a lower risk of death, although the risk of EGPA recurrence is significantly higher.

Dupilumab for relapsing or refractory sinonasal and/or asthma manifestations in eosinophilic granulomatosis with polyangiitis: a European retrospective study

BACKGROUND

Eosinophilic granulomatosis with polyangiitis (EGPA) is often associated with glucocorticoid-dependent asthma and/or ear, nose and throat (ENT) manifestations. When immunosuppressants and/or mepolizumab are ineffective, dupilumab could be an option. We describe the safety and efficacy of off-label use of dupilumab in relapsing and/or refractory EGPA.

PATIENTS AND METHODS

We conducted an observational multicentre study of EGPA patients treated with dupilumab. Complete response was defined by Birmingham Vasculitis Activity Score (BVAS)=0 and prednisone dose ≤4 mg/day, and partial response by BVAS=0 and prednisone dose >4 mg/day. Eosinophilia was defined as an eosinophil count >500/mm3.

RESULTS

Fifty-one patients were included. The primary indication for dupilumab was disabling ENT symptoms in 92%. After a median follow-up of 13.1 months, 18 patients (35%) reported adverse events (AEs), including two serious AEs. Eosinophilia was reported in 34 patients (67%), with a peak of 2195/mm3 (IQR 1268-4501) occurring at 13 weeks (IQR 4-36) and was associated with relapse in 41%. Twenty-one patients (41%) achieved a complete response and 12 (24%) a partial response. Sixteen (31%) patients experienced an EGPA relapse while on dupilumab, which was associated with blood eosinophilia in 14/16 (88%) patients. The median eosinophil count at the start of dupilumab was significantly lower in relapsers than in non-relapsers, as was the median time between stopping anti-IL-5/IL-5R and switching to dupilumab.

CONCLUSION

These results suggest that dupilumab may be effective in treating patients with EGPA-related ENT manifestations. However, EGPA flares occurred in one-third of patients and were preceded by eosinophilia in 88%, suggesting that caution is required.

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.

Cluster Analysis to Explore Clinical Subphenotypes of Eosinophilic Granulomatosis With Polyangiitis

OBJECTIVE

Previous studies suggested that distinct phenotypes of eosinophilic granulomatosis with polyangiitis (EGPA; formerly known as Churg-Strauss syndrome) could be determined by the presence or absence of antineutrophil cytoplasmic antibodies (ANCA), reflecting predominant vasculitic or eosinophilic processes, respectively. This study explored whether ANCA-based clusters or other clusters can be identified in EGPA.

METHODS

This study used standardized data of 15 European centers for patients with EGPA fulfilling widely accepted classification criteria. We used multiple correspondence analysis, hierarchical cluster analysis, and a decision tree model. The main model included 10 clinical variables (musculoskeletal [MSK], mucocutaneous, ophthalmological, ENT, cardiovascular, pulmonary, gastrointestinal, renal, central, or peripheral neurological involvement); a second model also included ANCA results.

RESULTS

The analyses included 489 patients diagnosed between 1984 and 2015. ANCA were detected in 37.2% of patients, mostly perinuclear ANCA (85.4%) and/or antimyeloperoxidase (87%). Compared with ANCA-negative patients, those with ANCA had more renal (P < 0.001) and peripheral neurological involvement (P = 0.04), fewer cardiovascular signs (P < 0.001), and fewer biopsies with eosinophilic tissue infiltrates (P = 0.001). The cluster analyses generated 4 (model without ANCA) and 5 clusters (model with ANCA). Both models identified 3 identical clusters of 34, 39, and 40 patients according to the presence or absence of ENT, central nervous system, and ophthalmological involvement. Peripheral neurological and cardiovascular involvement were not predictive characteristics.

CONCLUSION

Although reinforcing the known association of ANCA status with clinical manifestations, cluster analysis does not support a complete separation of EGPA in ANCA-positive and -negative subsets. Collectively, these data indicate that EGPA should be regarded as a phenotypic spectrum rather than a dichotomous disease.

Anti-neutrophil Cytoplasmic Antibody-negative Eosinophilic Granulomatosis with Polyangiitis Complicated with Peripheral Neuropathy that Underwent Remission Induction with Mepolizumab Monotherapy

A 72-year-old woman was admitted to our hospital with numbness in her lower extremities and hypereosinophilia. She was diagnosed with eosinophilic granulomatosis with polyangiitis (EGPA). On admission, she was suspected of being complicated with pneumonia and sepsis; therefore, treatment with mepolizumab monotherapy was begun, resulting in partial improvement. After the possibility of a complicating infection was ruled out, corticosteroids were initiated, followed by intravenous gamma globulin therapy. Although the induction of remission of EGPA with mepolizumab monotherapy is not usually recommended, induction with mepolizumab monotherapy may be an option in terms of safety and clinical efficacy in some cases.

Renal involvement in eosinophilic granulomatosis with polyangiitis

Eosinophilic granulomatosis with polyangiitis (EGPA) is a necrotizing vasculitis, which typically affects small-to medium-sized blood vessels. It is characterized by the presence of tissue infiltrates rich in eosinophils, along with the formation of granulomatous lesions. About 40% of cases have positive anti-neutrophil cytoplasm antibodies (ANCA), with predominant perinuclear staining, and anti-myeloperoxidase (anti-MPO) specificity in about 65% of cases. Typical manifestations of EGPA include the late onset of asthma, nasal and sinus-related symptoms, peripheral neuropathy, and significant eosinophilia observed in the peripheral blood. In contrast to granulomatosis with polyangiitis and microscopic polyangiitis, renal involvement in EGPA is less frequent (about 25%) and poorly studied. Necrotizing pauci-immune crescentic glomerulonephritis is the most common renal presentation in patients with ANCA-positive EGPA. Although rarely, other forms of renal involvement may also be observed, such as eosinophilic interstitial nephritis, mesangial glomerulonephritis, membranous nephropathy, or focal sclerosis. A standardized treatment for EGPA with renal involvement has not been defined, however the survival and the renal outcomes are usually better than in the other ANCA-associated vasculitides. Nonetheless, kidney disease is an adverse prognostic factor for EGPA patients. Larger studies are required to better describe the renal involvement, in particular for patterns different from crescentic glomerulonephritis, and to favor the development of a consensual therapeutic approach. In this article, in addition to personal data, we will review recent findings on patient clinical phenotypes based on ANCA, genetics and the impact of biological drugs on disease management.

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.

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.

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.

Evidence-Based Guideline for the diagnosis and management of eosinophilic granulomatosis with polyangiitis

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, characterized by asthma, eosinophilia and granulomatous or vasculitic involvement of several organs. The diagnosis and management of EGPA are often challenging and require an integrated, multidisciplinary approach. Current practice relies on recommendations and guidelines addressing the management of ANCA-associated vasculitis and not specifically developed for EGPA. Here, we present evidence-based, cross-discipline guidelines for the diagnosis and management of EGPA that reflect the substantial advances that have been made in the past few years in understanding the pathogenesis, clinical subphenotypes and differential diagnosis of the disease, as well as the availability of new treatment options. Developed by a panel of European experts on the basis of literature reviews and, where appropriate, expert opinion, the 16 statements and five overarching principles cover the diagnosis and staging, treatment, outcome and follow-up of EGPA. These recommendations are primarily intended to be used by healthcare professionals, pharmaceutical industries and drug regulatory authorities, to guide clinical practice and decision-making in EGPA. These guidelines are not intended to limit access to medications by healthcare agencies, nor to impose a fixed order on medication use.

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.

Advances in the pharmacotherapeutic management of eosinophilic granulomatosis with polyangiitis

INTRODUCTION

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare but potentially lethal systemic vasculitis. Only a few prospective therapeutic trials had been conducted in EGPA, and its treatment was mostly adapted from other vasculitides. Monoclonal antibodies inhibiting various pathways (e.g. interleukin-5 [IL5] or B cells) have been investigated.

AREAS COVERED

Published studies on treatments for EGPA using glucocorticoids, conventional immunosuppressants (such as cyclophosphamide or azathioprine), antiIL5 pathway agents (mepolizumab, approved by the Food and Drug Administration (FDA) and European Medicines Agency (EMA) for EGPA; benralizumab and reslizumab), other and future possible treatments [PubMed search, 01/1990-02/2023] are reviewed.

EXPERT OPINION

With advances made in the pharmacotherapeutic management of EGPA, the prognosis has gradually shifted from a potentially fatal to a more chronic course, for which more targeted and safer treatments can be used. However, glucocorticoids remain central. Rituximab is now a possible alternative to cyclophosphamide for induction, although data are still limited. AntiIL5 pathway therapies have been shown to be safe and effective in relapsing patients with EGPA, who often experience asthma and/or ears, nose, and throat (ENT) manifestations, but long-term data are needed. Treatment strategies need to be optimized based on individual patient characteristics, likely with sequential, combination-based approaches, while topical airway treatments should not be forgotten.

Eosinophilic Lung Diseases

The eosinophilic lung diseases may manifest as chronic eosinophilic pneumonia, acute eosinophilic pneumonia, or as the Löffler syndrome (generally of parasitic etiology). The diagnosis of eosinophilic pneumonia is made when both characteristic clinical-imaging features and alveolar eosinophilia are present. Peripheral blood eosinophils are generally markedly elevated; however, eosinophilia may be absent at presentation. Lung biopsy is not indicated except in atypical cases after multidisciplinary discussion. The inquiry to possible causes (medications, toxic drugs, exposures, and infections especially parasitic) must be meticulous. Idiopathic acute eosinophilic pneumonia may be misdiagnosed as infectious pneumonia. Extrathoracic manifestations raise the suspicion of a systemic disease especially eosinophilic granulomatosis with polyangiitis. Airflow obstruction is frequent in allergic bronchopulmonary aspergillosis, idiopathic chronic eosinophilic pneumonia, eosinophilic granulomatosis with polyangiitis, and hypereosinophilic obliterative bronchiolitis. Corticosteroids are the cornerstone of therapy, but relapses are common. Therapies targeting interleukin 5/interleukin-5 are increasingly used in eosinophilic lung diseases.

[Eosinophilia: hypereosinophilic syndrome vs. eosinophilic granulomatosis with polyangiitis]

Hypereosinophilic syndrome (HES) is defined as a peripheral eosinophil count of > 1500/μl (assessed twice at an interval of ≥ 2 weeks) and an eosinophil-induced organ damage. Idiopathic HES is differentiated from primary (clonal or neoplastic) HES and secondary (reactive) HES, depending on the etiology. Eosinophilic granulomatosis with polyangiitis (EGPA) is categorized as a secondary form of HES and is characterized by hypereosinophilia and vasculitis of small to medium-sized vessels and can be associated with an antineutrophil cytoplasmic antibody (ANCA). The treatment of HES is dependent on the etiology. Clonal HES is treated according to the respective genetic aberration, e.g. with tyrosine kinase inhibitors or chemotherapy and allogenic stem cell transplantation. Secondary forms should be treated according to the underlying cause (e.g. parasitic infection). The treatment of EGPA is carried out with immunosuppressants depending on the disease stage and disease activity. Conventional drugs, such as glucocorticoids (GC), cyclophosphamide (CYC) and methotrexate (MTX) or biologics, such as the monoclonal anti-IL5 antibody mepolizumab are commonly used. Mepolizumab is also a good option for the treatment of idiopathic HES.

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.

Multiple brain infarctions and endomyocarditis in ANCA-negative eosinophilic granulomatosis with polyangiitis

Eosinophilic granulomatosis with polyangiitis (EGPA) is a small vessel necrotizing vasculitis characterized by asthma and eosinophilia. Ischemic stroke is a rare complication of the disease. We herein report a case involving a 77-year-old woman with sinusitis who developed embolic stroke and splenic infarctions. Laboratory tests revealed hypereosinophilia and elevated troponin-T and N-terminal pro-brain natriuretic peptide. Antineutrophil cytoplasmic antibodies (ANCA) studies were negative. Skin biopsy showed infiltration of eosinophils into the arterial walls. These clinicopathological findings led to the diagnosis of EGPA. We also found the evidence of endomyocarditis as revealed by multimodality cardiac imaging. The patient underwent continuous immunosuppressive and anticoagulation therapy, and the infarctions did not recur. This report highlights the importance of histologically proven vasculitis with eosinophil infiltration and careful examination for cardiac involvement, especially in ANCA-negative patients.

A Review of Anti-IL-5 Therapies for Eosinophilic Granulomatosis with Polyangiitis

Eosinophilic granulomatosis with polyangiitis (EGPA), previously known as Churg-Strauss syndrome, is a systemic disorder characterized by asthma, eosinophilia, and vasculitis primarily affecting small vessels. Although this disease is classified as an anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis along with microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA), observations suggest that eosinophils play a vital role in the pathophysiology of EGPA. Therefore, biopsy specimens derived from patients with EGPA demonstrated an increase in eosinophils within the vascular lumen and extravascular interstitium, especially in patients negative for ANCA. In addition, active secretion of eosinophil intracellular components by cytolysis and piecemeal degranulation occurs in the extravascular interstitium and bloodstream. Although the treatment for EGPA is described in the context of ANCA-associated vasculitis along with MPA and GPA, a therapeutic approach to suppress eosinophils is also considered. Monoclonal antibodies directed against interleukin-5 (IL-5) or its receptors are good therapeutic agents because IL-5 plays an important role in eosinophil growth, activation, and survival. Currently, mepolizumab (Nucala), reslizumab (Cinqair), and benralizumab (Fasenra) have been studied for use in patients with EGPA. These monoclonal antibodies were initially approved for use in patients with severe eosinophilic asthma. Mepolizumab is now approved for treating EGPA following the success of phase 3 randomized controlled trial. Therefore, further studies are needed to clarify long-term safety and efficacy of anti-IL-5 agents and establish indications of individual therapeutic agents tailored to individual conditions of patients with EGPA.

Eosinophilic granulomatosis with polyangiitis: A review

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare, multi-system, inflammatory disease, belonging to the group of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV). Previously known as Churg-Strauss syndrome, EGPA is characterised by late-onset asthma, eosinophilia and vasculitis affecting small-to-medium vessels. This disease behaves differently in many aspects to the other AAV and is often excluded from AAV studies. The disease is poorly understood and, due to it rarity and unique manifestations, there has been limited research progress to optimise our understanding of its complex pathogenesis and ability to develop management options - although the success of interleukin-5 inhibitors such as Mepolizumab has been a welcome development. The pathophysiology also appears to be different to other forms of AAV and hence management strategies that work for AAV may not fully apply to this condition. There is no current standard therapy for EGPA although corticosteroids are almost universally used for treatment alongside other agents and encouraging modes of treatment continue to evolve beyond glucocorticoid immunosuppression (including interleukin-5 inhibition). There is therefore a significant ongoing unmet need for efficacious steroid-sparing immunosuppressing agents. The prognosis also diverges from other forms of AAV, and we discuss the pathophysiology, clinical features and diagnosis, management and prognosis in this article.

Vasculitis and Kidney Disease

Pediatric vasculitis is a complex group of disorders that commonly presents with multisystem involvement. Renal vasculitis can be isolated to the kidneys or can occur as part of a broader multiorgan vasculitis. Depending on severity, renal vasculitis may present as acute glomerulonephritis (AGN) often associated with hypertension and sometimes with a rapidly deteriorating clinical course. Prompt diagnosis and initiation of therapy are key to preserving kidney function and preventing long-term morbidity and mortality. This review focuses on the clinical presentation, diagnosis, and treatment objectives for common forms of renal vasculitis seen in pediatric patients.

Distinct features of hypereosinophilic syndrome with neuropathy from eosinophilic granulomatosis with polyangiitis

BACKGROUND AND OBJECTIVES

Hypereosinophilic syndrome (HES) and eosinophilic granulomatosis with polyangiitis (EGPA) have overlapping clinical considerations, which frequently involve peripheral neuropathy. The current study aimed to discriminate between the clinicopathological features of HES and EGPA, focusing on the mechanism of peripheral nerve damage.

METHODS

A total of 53 patients who underwent nerve biopsies at our laboratory were examined: nine patients with idiopathic HES (iHES), three patients with reactive HES, 14 patients with myeloperoxidase-anti-neutrophil cytoplasmic antibody (ANCA)-positive EGPA, and 27 patients with negative EGPA. Nerve biopsies were performed using light and electron microscopy.

RESULTS

Polyneuropathy was more common than mononeuritis multiplex in iHES, which differed from that in ANCA-negative EGPA groups (p = 0.012). Nerve biopsies showed that iHES was associated with neuropathy features such as rare vasculitis and non-vasculitic eosinophilic infiltrates, which differed from those of ANCA-negative EGPA. Fibrinoid necrosis was found only in the reactive HES and ANCA-positive groups. The percentage of endoneurial vessels occluded with eosinophils tended to be higher in iHES (1.8%) than in ANCA-positive EGPA (0%) and negative EGPA (0.7%). In a patient with ANCA-negative EGPA, the endoneurial vessels were occluded with platelets, fibrinoid materials, and eosinophils, demonstrating the morphology of eosinophil extracellular traps.

CONCLUSION

iHES with neuropathy showed a pattern more similar to polyneuropathy than mononeuritis multiplex, which is dominant in ANCA-negative EGPA, and tended to show vasculitis in the peripheral nerves less frequently compared with EGPA. Eosinophilic infiltration and endoneurial vascular occlusion by eosinophils may cause nerve damage.

At the Heart of Eosinophilic Granulomatosis with Polyangiitis: into Cardiac and Vascular Involvement

PURPOSE OF REVIEW

To provide an overview of existing literature on pathogenetic and clinical aspects of cardiac and vascular involvement in eosinophilic granulomatosis with polyangiitis (EGPA).

RECENT FINDINGS

In EGPA, cardiac and vascular involvement are more common than previously thought. However, no international recommendations on the topic are available yet. Herein, we summarize the existing evidence on the topic and propose a diagnostic approach for cardiac involvement in EGPA. The prevalence of cardiovascular involvement in patients with EGPA varies greatly among published studies, ranging between 3.1-18.7% for occlusive arterial disease, 5.8-30% for venous thrombosis and 17-92% for heart involvement. Cardiac involvement in EGPA is associated with high mortality even though manifestations are heterogeneous. In principle, every anatomical structure of the heart can be involved, and EGPA-related heart disease may be completely asymptomatic at first. A careful diagnostic work-up for early detection and prompt treatment initiation is therefore required. While cardiac manifestations are more common in anti-neutrophil cytoplasmic antibodies (ANCA)-negative patients, arterial and venous thrombotic events are not linked to ANCA status but correlate closely with disease activity and accumulate at disease onset. Thrombotic events (mainly venous) are considerably more frequent in EGPA than in the general population contributing substantially to morbidity and highlighting the importance of developing specific prevention strategies for patients who are diagnosed with EGPA.

Current perspectives on the diagnosis, assessment, and management of vasculitic neuropathy

INTRODUCTION

Vasculitic neuropathy can present associated with both primary and secondary systemic vasculitis as a result from underlying diseases such as rheumatic diseases and infections, Moreover, confined vasculitis in the peripheral nervous system may be present. Thus, the diagnosis and management of vasculitic neuropathy require multidisciplinary approaches.

AREAS COVERED

Current views as well as relevant clinical research on the diagnosis, assessment, and management of vasculitic neuropathy are reviewed to suggest appropriate treatment strategies. We searched PubMed and Google Scholar for reports published between July 2017 and July 2022.

EXPERT OPINION

For the treatment of vasculitic neuropathy, determining the causative primary disease is important and often requires diagnosis by tissue biopsy. Due to the scarce research on the treatment of vasculitic neuropathy, treatment is empirically based on findings from studies of systemic vasculitides involving other organs, particularly antineutrophil cytoplasmic antibody-associated vasculitis. In addition to conventional glucocorticoids and immunosuppressive agents, complement-targeted therapy, anti-B-cell therapy, and disease-specific molecular targeted therapies have recently gained relevance. Future research is needed to develop new patient-specific therapeutic options.

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.

Genetics of ANCA-associated vasculitis: role in pathogenesis, classification and management

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) comprises granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (EGPA), that share features of pauci-immune small-vessel vasculitis and the positivity of ANCA targeting proteinase-3 (PR3-ANCA) or myeloperoxidase (MPO-ANCA). AAV syndromes are rare, complex diseases and their aetio-pathogenesis is mainly driven by the interaction between environmental and genetic factors. In patients with GPA and MPA, the genetic associations are stronger with ANCA specificity (PR3- versus MPO-ANCA) than with the clinical diagnosis, which, in keeping with the known clinical and prognostic differences between PR3-ANCA-positive and MPO-ANCA-positive patients, supports an ANCA-based re-classification of these disorders. EGPA is also made up of genetically distinct subsets, which can be stratified on ANCA-status (MPO ANCA-positive versus ANCA-negative); these subsets differ in clinical phenotype and possibly in their response to treatment. Interestingly, MPO-ANCA-positive patients with either MPA or EGPA have overlapping genetic determinants, thus strengthening the concept that this EGPA subset is closely related to the other AAV syndromes. The genetics of AAV provides us with essential information to understand its varied phenotype. This Review discusses the main findings of genetic association studies in AAV, their pathogenic implications and their potential effect on classification, management and prognosis.

Long-term Safety and Efficacy of Benralizumab for Eosinophilic Granulomatosis with Polyangiitis Complicated with Severe Neuropathy

The efficacy of benralizumab, as well as mepolizumab, to granulomatosis with polyangiitis (EGPA) involved with mononeuritis multiplex remains unclear. We experienced a case of EGPA presenting neuropathy with severe asthma. Muscle weakness due to neuropathy involved with gait disturbance was partly ameliorated by intravenous immunoglobulin therapy. Mepolizumab (100 mg/day) did not promote further improvement of neuropathy. However, the administration of benralizumab instead of mepolizumab improved neuropathy quickly and enabled walking alone. The efficacy of benralizumab for EGPA and its complication has been maintained for over four years. Benralizumab may be a possible treatment for EGPA presenting neuropathy with severe asthma.

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.

A diagnostic score for eosinophilic granulomatosis with polyangiitis among eosinophilic disorders

BACKGROUND

Eosinophilic granulomatosis with polyangiitis (EGPA) is a form of systemic vasculitis with eosinophilic inflammation. However, existing classification criteria are all designed to classify EGPA among vasculitis and there is no established method distinguishing EGPA from other eosinophilic disorders. The aim of the present study was to propose a scoring system to differentiate EGPA among eosinophilic disorders.

METHODS

Non-supervised hierarchical clustering using Ward's method and principal component analysis (PCA) were performed for 19 clinical parameters of 58 patients with eosinophilia-related diseases at a tertiary university hospital. The newly proposed scoring system was externally validated in 40 patients at another tertiary institution.

RESULTS

Two distinct clusters were identified, and clinical features including peripheral neuropathy, asthma, skin involvement, lung involvement, rheumatoid factor (RF) positivity, myeloperoxidase (MPO)-anti-neutrophil cytoplasmic antibody (ANCA) positivity, IgE elevation, C-reactive protein (CRP) elevation, and vasculitis pathological findings were predominantly observed in one of these clusters (p < 0.05). Ten features defining the cluster with a high rate of vasculitis were weighted by PCA to create the E-CASE (EGPA classification among systemic eosinophilia) scoring system, on a 16-point scale. Based on the distribution of scores in the primary cohort, we defined an E-CASE score ≥12 as positive, ≤ 8 as negative, and 9-11 as undeterminable. The sensitivity and specificity of the E-CASE score in the validation cohort were 93.3% and 100%, respectively.

CONCLUSIONS

We developed and verified a novel scoring system for differentiating EGPA from other types of eosinophilic disorders.

The presentation, etiologies, pathophysiology, and treatment of pulmonary renal syndrome: A review of the literature

Pulmonary renal syndrome (PRS) is a constellation of different disorders that cause both rapidly progressive glomerulonephritis and diffuse alveolar hemorrhage. While antineutrophil cytoplasmic antibody associated vasculitis and anti-glomerular basement membrane disease are the predominant causes of PRS, numerous other mechanisms have been shown to cause this syndrome, including thrombotic microangiopathies, drug exposures, and infections, among others. This syndrome has high morbidity and mortality, and early diagnosis and treatment is imperative to improve outcomes. Treatment generally involves glucocorticoids and immunosuppressive agents, but treatment targeted to the underlying disorder can improve outcomes and mitigate side effects. Familiarity with the wide range of possible causes of PRS can aid the clinician in workup, diagnosis and early initiation of treatment. This review provides a summary of the clinical presentation, etiologies, pathophysiology, and treatment of PRS.

Intractable middle ear effusion in EGPA patients might cause permanent hearing loss: a case-control study

Background

Ear, nose, and throat involvement are common in eosinophilic granulomatosis with polyangiitis (EGPA). Among otologic manifestation, middle ear effusion (MEE) is less recognized but a problematic condition as it may progress to hearing impairment when left untreated. This study aimed to evaluate the characteristics, risk factors and clinical outcomes of MEE in EGPA patients.

Methods

This is a case–control study of patients who were diagnosed and treated for EGPA from January 1995 to November 2018. Patients with ear symptoms (ear fullness, ear discharge, tinnitus or hearing loss) were assessed by otologists and were included in the case group (n = 23) if clinically relevant. The other patients without MEE were included in the control group (n = 52). Risk of MEE was calculated using the Cox proportional-hazard model.

Results

During median follow-up of 9.9 years, 23 (30.7%) out of 75 patients had MEE. In MEE group, 12 (52.2%) patients had hearing loss; conductive type in 10 (10/12, 83.3%) and mixed type in two (2/12, 16.7%). In multivariable regression analysis, major organ involvement at diagnosis (adjusted hazard ratio [aHR] 65.4; 95% confidence interval [CI], 1.50—2838.39; P = 0.030] , early onset of ear symptom after systemic therapy (< 6 months) (aHR 40.0; 95% CI, 1.35—1183.43; P = 0.033) and continuing the maintenance steroid without cessation (aHR 8.59; 95% CI, 1.13—65.42; P = 0.038) were independently associated with a risk of MEE. To control MEE, 16 (69.6%) patients had to increase maintenance steroid dose and 9 (39.1%) patients experienced recurrent MEE whenever maintenance dose was tapered.

Conclusions

MEE is a common but frequently neglected condition in EGPA which is often intractable. The maintenance steroid dose should be adequately adjusted to control MEE and to prevent from progressive hearing loss. Novel biologic agents possibly have a role in controlling MEE in EGPA.

Clinical Significance of MPO-ANCA in Eosinophilic Granulomatosis With Polyangiitis: Experience From a Longitudinal Chinese Cohort

Objectives

The aim of this study is to investigate the clinical significance of myeloperoxidase (MPO)–antineutrophil cytoplasmic antibody (ANCA) on eosinophilic granulomatosis with polyangiitis (EGPA) from a longitudinal Chinese cohort.

Methods

A total of 120 patients with EGPA were consecutively enrolled and followed up. Two patients with PR3 ANCA was excluded and our analysis focused on the 118 patients with EGPA. On the basis of MPO-ANCA status, baseline clinical manifestations, treatment, and outcomes were analyzed. Logistic regression analysis was performed to analyze the independently associated factors for renal involvement.

Results

ANCA positivity was observed in 24.2% of patients with EGPA. Patients with MPO-ANCA accounted for 20.8%. Patients with positive MPO-ANCA had higher levels of erythrocyte sedimentation rate (ESR), C-reactive protein, Birmingham Vasculitis Activity Score (BVAS), higher ratios of fever, myalgia, renal involvement, and biopsy-proven vasculitis. Heart manifestations and asthma were more common in patients with negative ANCA. Baseline MPO-ANCA titers positively correlated with ESR, eosinophil count, and BVAS and were higher in patients with methylprednisolone pulse. Among patients with renal involvement, patients with positive MPO-ANCA had higher proportions of female, fever, biopsy-proven vasculitis, and faster ESR; patients with negative ANCA developed more skin and cardiac involvement. MPO-ANCA positivity, male, and ear involvement were the independent factors associated with renal involvement. Intravenous cyclophosphamide and immunoglobulins were prescribed more frequently in patients with positive MPO-ANCA.

Conclusion

In this cohort, patients with positive MPO-ANCA and negative ANCA displayed distinct clinical features, suggesting that MPO-ANCA might be a valuable biomarker for EGPA stratification. Baseline MPO-ANCA level correlated positively with disease activity of EGPA. MPO-ANCA was a significant independent factor associated with renal involvement.

Self-Reported Data and Physician-Reported Data in Patients With Eosinophilic Granulomatosis With Polyangiitis: Comparative Analysis

Background

Patient-based registries can help advance research on rare diseases such as eosinophilic granulomatosis with polyangiitis (EGPA), a complex multiorgan form of antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis.

Objective

The aim of this study is to compare patient-reported and physician-reported data on manifestations, treatments, and outcomes for patients with EGPA.

Methods

We completed a comparative analysis of patients ≥18 years with EGPA in Canada and the United States from the following 2 cohorts: (1) The Vasculitis Patient-Powered Research Network (VPPRN), a self-enrolled secure portal with patient-entered data updated quarterly (2014-2019) and (2) the Vasculitis Clinical Research Consortium (VCRC) observational studies, a physician-entered database (2003-2019) of patients who fulfilled the 1990 American College of Rheumatology classification criteria for EGPA. The studied parameters included demographic characteristics, clinical manifestations, ANCA status, treatments, and relapses.

Results

Data from 195 patients with a validated diagnosis of EGPA in the VPPRN and 354 patients enrolled in the VCRC were analyzed. Compared to the VCRC cohort, the patients in the VPPRN cohort were more likely to be female (135/195, 69.2% compared to 209/354, 59%; P=.02) and younger at diagnosis (47.3 compared to 50.0 years; P=.03); both cohorts reported similar frequencies of asthma (177/184, 96.2% in the VPPRN cohort compared to 329/354, 92.9% in the VCRC cohort; P=.13) and cardiac manifestations (44/153, 28.8% compared to 75/354, 21.2%; P=.06), but the VPPRN cohort reported less frequent lung manifestations other than asthma and more frequent disease manifestations in all other organ systems. The ANCA positivity was 48.9% (64/131) in the VPPRN patients compared to 38.9% (123/316; P=.05) in the VCRC cohort. Relapsing disease after study enrollment was reported in 32.3% (63/195) of patients in the VPPRN compared to 35.7% (99/277) of patients in the VCRC. Most therapies (GC, cyclophosphamide, mepolizumab) were used at similar frequencies in both groups, except for rituximab with VPPRN patients reporting more use than the VCRC cohort (47/195, 24.1% compared to 29/277, 10.5%; P<.001).

Conclusions

Overall, patients and physicians report manifestations of EGPA at similar frequencies. However, observed differences between patient and physician reports imply the potential occurrence of selection biases. These results support the use of patient-reported data in EGPA but also the need for careful consideration of disease-specific definitions for the study of EGPA and how patient- and physician-reported data are collected.

Trial Registration

ClinicalTrials.gov NCT00315380, https://clinicaltrials.gov/ct2/show/NCT00315380; ClinicalTrials.gov NCT01241305, https://clinicaltrials.gov/ct2/show/NCT01241305

ANCA-Negative Vasculitis in Eosinophilic Granulomatosis with Polyangiitis Complicated with Membranous Nephropathy: A Case Report and Brief Literature Review

Renal involvement in eosinophilic granulomatosis with polyangiitis (EGPA) typically occurs in anti-neutrophil cytoplasmic autoantibody (ANCA)-positive cases presenting with rapidly progressive renal insufficiency and urinary abnormalities induced by primarily necrotizing crescentic glomerulonephritis (NCGN). Recently, ANCA-negative EGPA has also been reported to manifest with renal involvement, such as NCGN or non-NCGN, including membranous nephropathy (MN). Herein, we report a 70-year-old female who presented with purpura on the lower legs, upper limb numbness, renal dysfunction (eGFR, 20.5 ml/min/1.73 m2), and eosinophilia (eosinophils, 37,570/μl). MPO-and PR3-ANCA were negative, and urinalysis revealed urine protein (0.63 g/day) but without red blood cells in the urine sediment. Thus, she was diagnosed with ANCA-negative EGPA with rapidly progressive renal dysfunction. A renal biopsy revealed vasculitis in the interlobular arteries without NCGN, with the vasculitis being complicated by MN. Micrograph findings on fluorescence immunostaining contained both primary and secondary characteristics of MN (dominance of IgG subclass 4 more than subclass 1 vs. negativity of PLA2R and THSD7A). After treatment with prednisolone, her eosinophil counts normalized, and renal dysfunction improved. Furthermore, urine protein did not increase above 1.0 g/day during the clinical course. This is a rare case of ANCA-negative EGPA presenting with acute renal dysfunction without NCGN and subclinical MN with unknown etiology. It is important to recognize that EGPA pathology varies widely throughout the disease course, and the clinical course of subclinical MN should be carefully assessed in further follow-ups.

In vivo visualization of eosinophil secretion in eosinophilic granulomatosis with polyangiitis: An ultrastructural study

BACKGROUND

Although eosinophilic granulomatosis with polyangiitis (EGPA) has been considered as a single disease entity belonging to anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, several studies have suggested that in addition to the mechanisms associated with ANCA, those associated with eosinophils play a vital role in tissue damage. Nevertheless, the morphological bases underlying eosinophil-associated lesions have not been completely elucidated.

METHODS

We investigated the electron microscopic findings of sural nerve biopsy specimens obtained from 18 patients with EGPA by focusing on the behavior of eosinophils, particularly the mode of secretion.

RESULTS

Eosinophils tended to be located at sites close to endothelial cells within the lumina of epineurial small vessels. Attachment of eosinophils to endothelial cells was observed, particularly at the junction between neighboring endothelial cells, and some of these eosinophils appeared to escape from the vascular lumen to migrate into the extravascular interstitium. Furthermore, we observed eosinophil degranulation via piecemeal degranulation and cytolysis. Degranulating eosinophils were identified in both intravascular and extravascular compartments. Some of the small vessels appeared to be occluded by numerous eosinophils, and eosinophils attached by platelets were also observed, suggesting that coagulopathy occurs in EGPA.

CONCLUSIONS

Both extravascular and intravascular eosinophils can induce tissue damage unrelated to classical necrotizing vasculitis associated with ANCA in patients with EGPA. Further research is necessary to elucidate the molecular basis of the induction of these fine structural changes, which will contribute to the development of targeted therapies based on specific mechanisms of eosinophil-related diseases.

Case Report: Severe Eosinophilic Asthma Associated With ANCA-Negative EGPA in a Young Adult Successfully Treated With Benralizumab

Background: Traditionally, Eosinophilic Granulomatosis with Polyangiitis (EGPA) has been treated with systemic corticosteroids and immunosuppressants. In recent years, therapeutic efforts have been directed towards targeting eosinophils which represent a major player in the pathogenesis of EGPA. In 2017 the Food and Drug Administration (FDA) approved mepolizumab, a humanized monoclonal antibody targeting interleukin 5 (IL-5) which reduces the production and survival of eosinophils, already used to treat severe eosinophilic asthma, for the management of EGPA. Benralizumab is a humanized monoclonal antibody that targets the IL-5 receptor and is indicated in the treatment of severe eosinophilic asthma.

Case description: We describe the case of a young female with a positive history of severe eosinophilic asthma associated with EGPA, treated successfully with benralizumab.

The clinical features and treatment of eosinophilic granulomatosis with polyangiitis (EGPA) in Turkey: one or two distinct diseases?

Eosinophilic granulomatosis with polyangiitis (EGPA) is defined the disease as having two subgroups, ANCA (+) and ANCA (-). We aimed to compare EGPA subgroups in terms of clinical features, outcomes, and treatments. A multidisciplinary team was established under our vasculitis centre since October 2014. Totally 50 EGPA patients were enrolled. Clinical features, treatments, and outcomes (FFS, VDI, relapse) were reviewed. For relapse-free survival analysis, time to first relapse was compared according to ANCA phenotype by Kaplan-Meier survival analysis and log-rank test. 17 (34%) patients were in ANCA (+), 33 (66%) patients were in ANCA (-) group. ANCA (-) patients were significantly younger at the diagnosis time (37.9 ± 14.3 vs 53.8 ± 16.3; p = 0.001) and had more nasal polyposis (45.5% vs 11.8%; p = 0.017). ANCA (+) patients had higher BVAS (17[13] vs 9[4]; p = 0.002), renal involvement and peripheral neuropathy were more common in this group, while cardiac involvement was seen only in ANCA (-) group (n = 3). Biological agents (mepolizumab or rituximab) were prescribed to nine patients in ANCA (-) and two patients in ANCA (+) group. The median duration of follow-up was 47 (IQR 69.9) months. ~ 40% of patients had at least one relapse, but relapse-free survival rate was similar between the groups. However, the predictor of first relapse was elevated Ig E level [OR (95% CI): 6.5 (1.09-38.63) p = 0.04]. Consequently, both clinical features, disease activity, and treatments appear to be significantly different between EGPA subgroups. The relapse risk was similar although clinical features and treatment strategies were different. Also, elevated Ig E levels may be a precursor for the relapse.

2022 American College of Rheumatology/European Alliance of Associations for Rheumatology Classification Criteria for Eosinophilic Granulomatosis With Polyangiitis

OBJECTIVE

To develop and validate revised classification criteria for eosinophilic granulomatosis with polyangiitis (EGPA).

METHODS

Patients with vasculitis or comparator diseases were recruited into an international cohort. The study proceeded in 5 phases: 1) identification of candidate criteria items using consensus methodology, 2) prospective collection of candidate items present at the time of diagnosis, 3) data-driven reduction of the number of candidate items, 4) expert panel review of cases to define the reference diagnosis, and 5) derivation of a points-based risk score for disease classification in a development set using least absolute shrinkage and selection operator logistic regression, with subsequent validation of performance characteristics in an independent set of cases and comparators.

RESULTS

The development set for EGPA consisted of 107 cases of EGPA and 450 comparators. The validation set consisted of an additional 119 cases of EGPA and 437 comparators. From 91 candidate items, regression analysis identified 11 items for EPGA, 7 of which were retained. The final criteria and their weights were as follows: maximum eosinophil count ≥1 × 10⁹ /liter (+5), obstructive airway disease (+3), nasal polyps (+3), cytoplasmic antineutrophil cytoplasmic antibody (ANCA) or anti-proteinase 3 ANCA positivity (-3), extravascular eosinophilic predominant inflammation (+2), mononeuritis multiplex/motor neuropathy not due to radiculopathy (+1), and hematuria (-1). After excluding mimics of vasculitis, a patient with a diagnosis of small- or medium-vessel vasculitis could be classified as having EGPA if the cumulative score was ≥6 points. When these criteria were tested in the validation data set, the sensitivity was 85% (95% confidence interval [95% CI] 77-91%) and the specificity was 99% (95% CI 98-100%).

CONCLUSION

The 2022 American College of Rheumatology/European Alliance of Associations for Rheumatology classification criteria for EGPA demonstrate strong performance characteristics and are validated for use in research.

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.

2022 American College of Rheumatology/European Alliance of Associations for Rheumatology Classification Criteria for Eosinophilic Granulomatosis with Polyangiitis

OBJECTIVE

To develop and validate revised classification criteria for eosinophilic granulomatosis with polyangiitis (EGPA).

METHODS

Patients with vasculitis or comparator diseases were recruited into an international cohort. The study proceeded in five phases: (1) identification of candidate criteria items using consensus methodology, (2) prospective collection of candidate items present at the time of diagnosis, (3) data-driven reduction of the number of candidate items, (4) expert panel review of cases to define the reference diagnosis and (5) derivation of a points-based risk score for disease classification in a development set using least absolute shrinkage and selection operator logistic regression, with subsequent validation of performance characteristics in an independent set of cases and comparators.

RESULTS

The development set for EGPA consisted of 107 cases of EGPA and 450 comparators. The validation set consisted of an additional 119 cases of EGPA and 437 comparators. From 91 candidate items, regression analysis identified 11 items for EPGA, 7 of which were retained. The final criteria and their weights were as follows: maximum eosinophil count ≥1×10⁹/L (+5), obstructive airway disease (+3), nasal polyps (+3), cytoplasmic antineutrophil cytoplasmic antibody (ANCA) or anti-proteinase 3-ANCA positivity (-3), extravascular eosinophilic predominant inflammation (+2), mononeuritis multiplex/motor neuropathy not due to radiculopathy (+1) and haematuria (-1). After excluding mimics of vasculitis, a patient with a diagnosis of small- or medium-vessel vasculitis could be classified as having EGPA if the cumulative score was ≥6 points. When these criteria were tested in the validation data set, the sensitivity was 85% (95% CI 77% to 91%) and the specificity was 99% (95% CI 98% to 100%).

CONCLUSION

The 2022 American College of Rheumatology/European Alliance of Associations for Rheumatology Classification Criteria for Eosinophilic Granulomatosis with Polyangiitis demonstrate strong performance characteristics and are validated for use in research.

[Eosinophilic granulomatosis with polyangiitis : Update on classification and management]

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare chronic inflammatory systemic disease that occurs in patients with bronchial asthma and is associated with significant blood and tissue eosinophilia. Another characteristic is vasculitis of small and/or medium-sized vessels, which may be absent in prodromal stages of the disease and is therefore no longer an obligatory part of the disease definition. Antineutrophil cytoplasmic antibodies (ANCA) can be detected in approximately one third of patients. The ANCA-positive and ANCA-negative EGPA are genetically distinct diseases with common clinical manifestations, which, however, occur with different frequencies. Cardiac involvement is associated with a poor prognosis. Permanent organ damage often occurs as a result of the underlying disease or treatment, especially with glucocorticoids (GC). The standard treatment of EGPA consists of GC in combination with cyclophosphamide for severe organ involvement or medium potency immunosuppressants for more prognostically favorable manifestations. Biologics are increasingly being used in the treatment of EGPA. The interleukin (IL) 5 antagonist mepolizumab reduces the risk of relapses and decreases the demand for GC in patients with relapsing EGPA without severe organ involvement. In analogy to the approach to other ANCA-associated vasculitides, the use of rituximab in ANCA-positive EGPA patients with severe vasculitis recurrence is a possible option, even though formal evidence for such an approach is currently low and formal approval is lacking.

ANCA-Associated Vasculitic Neuropathies: A Review

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a systemic disorder that frequently affects the peripheral nervous system and consists of three distinct conditions: microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA, previously Wegener’s granulomatosis), and eosinophilic granulomatosis with polyangiitis (EGPA, previously Churg-Strauss syndrome). The neuropathic features associated with this condition usually include mononeuritis multiplex, which reflects the locality of lesions. Findings suggestive of vasculitis are usually found in the epineurium and occur diffusely throughout the nerve trunk. Nerve fiber degeneration resulting from ischemia is sometimes focal or asymmetric and tends to become conspicuous at the middle portion of the nerve trunk. The attachment of neutrophils to endothelial cells in the epineurial vessels is frequently observed in patients with ANCA-associated vasculitis; neutrophils play an important role in vascular inflammation by binding of ANCA. The positivity rate of ANCA in EGPA is lower than that in MPA and GPA, and intravascular and tissue eosinophils appear to participate in neuropathy. Immunotherapy for ANCA-associated vasculitis involves the induction and maintenance of remission to prevent the relapse of the disease. A combination of glucocorticoids along with cyclophosphamide, rituximab, methotrexate, or mycophenolate mofetil is considered depending on the severity of the condition of the organ to induce remission. A combination of low-dose glucocorticoids and azathioprine, rituximab, methotrexate, or mycophenolate mofetil is recommended to maintain remission. The efficacy of anti-interleukin-5 therapy (i.e., mepolizumab) was demonstrated in the case of refractory or relapsing EGPA. Several other new agents, including avacopan, vilobelimab, and abatacept, are under development for the treatment of ANCA-associated vasculitis. Multidisciplinary approaches are required for the diagnosis and management of the disorder because of its systemic nature. Furthermore, active participation of neurologists is required because the associated neuropathic symptoms can significantly disrupt the day-to-day functioning and quality of life of patients with ANCA-associated vasculitis.