Antineutrophil Cytoplasmic Antibody Research Articles

P20 Persistent anti-PR3 ANCA positivity in patient with extrapulmonary tuberculosis

Abstract Introduction Granulomatosis with polyangiitis (GPA) and tuberculosis (TB) are both granulomatous disease which can have similar clinical manifestations and organ involvement. This report discusses a case of such overlapping clinical presentation and anti-neutrophil cytoplasmic antibodies (ANCA) positivity, leading to diagnostic uncertainty. Case description A 40-year-old female who lived in sub-Saharan Africa until two years ago presented with a two month history of general malaise, significant weight loss, severe anorexia, diarrhoea, vomiting and nausea. She had no night sweats, blood in stool, abdominal pain, respiratory or cardiac symptoms, sino-nasal symptoms, rashes or neurological features. On examination, she appeared severely malnourished. Blood tests revealed microcytic anaemia (Hb 83 g/l, MCV 69fl), thrombocytosis, hypoalbuminemia (15 g/l), CRP 26 mg/l, elevated procalcitonin (1.46 ug/l), elevated LDH 263U/l. She had a positive double-stranded DNA and anti-cardiolipin IgM. ANCA was moderately positive with an anti-PR3 titre of 78 U/ml. Computerised tomography (CT) chest to pelvis revealed widespread necrotic lymphadenopathy, bilateral pulmonary emboli with infarcts, pancolitis and non-specific gall bladder thickening. Endoscopy revealed inflamed featureless colon with no microscopic granulomata. Acid-fast bacilli were isolated on endobronchial ultrasound guided biopsy of the necrotic nodes leading to confirmation of the diagnosis of extrapulmonary disseminated tuberculosis. Clinical improvement and improvement in CRP and anti-PR3 titre (48 U/ml) were seen following two weeks of anti-tuberculous treatment and a weaning course of steroids for colitis. Discussion Often GPA and tuberculosis can have similar presentations including lung and gastrointestinal involvement along with lymphadenopathy. This case demonstrates how ANCA and PR3 positivity can also be a common feature in these two conditions. Correct diagnosis is crucial in preventing harm to the patient as a diagnosis of GPA would require prompt and aggressive immunosuppression which may result in disseminated mycobacterial infection in the case of misdiagnosis; similarly, anti-mycobacterial therapy is unlikely control systemic GPA. In our patient, although the enteritis, general malaise and weight loss can be features of vasculitis and tuberculosis, careful history suggested no convincing other features of GPA, including the absence of ear, nose, throat, skin, neurological or renal involvement. The social history yielded migration from sub-Saharan Africa where tuberculosis is much more prevalent. A useful distinguishing biochemical test was the elevated procalcitonin which points towards a bacterial infection rather than an autoimmune process. Ultimate conclusive evidence of mycobacterial infection requires either positive acid-fast bacilli on staining or culture; lymph node biopsy allowed us to promptly and correctly diagnose this patient in the absence of sputum or pulmonary tuberculosis. Initiation of anti-tuberculous treatment rapidly settled this patient’s symptoms with a falling CRP. This case report highlights the fact that tuberculosis can mimic ANCA-associated vasculitis with positive anti-PR3 antibodies. In such cases, careful history taking, appropriate imaging and positive acid fast bacilli on staining or culture from sputum or tissue are important for prompt diagnosis and treatment. Both disseminated tuberculosis and systemic GPA can be rapidly progressive and severe if untreated. Although literature described the co-existence of both conditions, this is very rare. Correct diagnosis is key in initiation of the widely different treatment strategies, with the treatment for GPA potentially causing harm in disseminated tuberculosis. Key learning points • ANCA positivity in tuberculosis has been documented in the literature and positive anti-PR3 cannot be used solely to diagnose GPA. Therefore, a thorough history, examination, imaging and tissue examination, including tuberculosis culture and acid-fast staining, are recommended.

Monoclonal Gammopathy in Patients with Neuropathy.

The incidence of monoclonal gammopathy of undetermined significance (MGUS) in the population of over 50-year-olds is approximately 3% and increases with age. The association between MG and neuropathy has been of interest for several years, but the causal relationship has not yet been clarified. For 682 patients who visited the Department of Neurology and requested tests for MG work-up, we retrospectively collected demographic and clinical information, such as age, gender, diagnosis, and neurologic and laboratory test results, from their medical records. Out of a total of 682 patients who were suspected of neuropathy and tested for monoclonal gammopathy (MG), twelve (1.76%) showed MG on their serum protein electrophoresis. The most common form was IgM-κ with five patients, followed by IgG-κ, IgG-λ, and biclonal IgG-λ and IgA-κ. The results of the immunoglobulin quantitation test and free light chain assay showed that involved M-protein values in these patients were increased. Some patients were positive for anti-myelin-associated glycoprotein (MAG) antibody, anti-GD1b IgM antibody, anti-GM1 IgG & IgM antibody, and anti-cardiolipin IgM antibody. Also, some had antinuclear antibody (ANA) or antineutrophil cytoplasmic antibody (ANCA). In the future, it is necessary to investigate the pathogenic relationship between M-protein and autoantibodies in patients with neuropathies.

Circulating Autoantibodies in Adults with Hashimoto’s Thyroiditis: New Insights from a Single-Center, Cross-Sectional Study

Background: Hashimoto’s thyroiditis (HT) is a common autoimmune thyroid disorder characterized by elevated anti-thyroid peroxidase (A-TPO) antibodies. HT frequently coexists with other autoimmune conditions, which are marked by organ-specific and non-organ-specific autoantibodies, reflecting a deregulated immune response. However, the burden and clinical significance of these circulating autoantibodies in adult patients with HT remains unclear. Methods: A cross-sectional study was conducted at the University Hospital “R. Dulbecco” in Catanzaro, Italy, from November 2023 to May 2024, involving 200 euthyroid adults. The study population comprised 100 A-TPO-positive HT patients and 100 A-TPO-negative controls, matched for age and sex. Laboratory assessments included thyroid function tests and detection of autoantibodies [e.g., antinuclear antibodies (ANA), anti-parietal cell antibodies (APCA), and anti-neutrophil cytoplasmic antibodies (ANCA)]. Cytokine profiles were also measured using sensitive chemiluminescent multi-array technology. Results: HT patients were predominantly female (77.0%) with a median age of 56 years. Compared to controls, HT patients had higher median thyroid stimulating hormone (TSH) levels (2.215 vs. 1.705 μIU/mL, p = 0.025). Circulating autoantibodies were more prevalent in the HT group, with higher rates of APCA positivity (16.3% vs. 4.1%, p = 0.008) and atypical ANCA positivity (27.3% vs. 10.2%, p = 0.003). This suggests an increased risk for autoimmune gastritis and systemic inflammation. Additionally, HT patients with positive atypical ANCA showed elevated inflammatory cytokines, particularly interleukin-1 alpha (IL-1α), in female patients (p = 0.035). Conclusions: HT is significantly associated with a higher prevalence of circulating autoantibodies, such as APCA and atypical ANCA, which may indicate a heightened risk for autoimmune gastritis and broader autoimmune involvement. Detecting these autoantibodies in HT patients could serve as markers for more severe autoimmune dysfunction. These findings emphasize the need for proactive screening, especially in older patients and those with elevated A-TPO levels. Further research is essential to better understand the clinical implications and develop targeted management strategies for these patients.

A case of systemic lupus erythematosus with antineutrophil cytoplasmic antibodies, positive skin vasculitis, and concomitant combined thrombophilia.

A case of systemic lupus erythematosus with antineutrophil cytoplasmic antibodies, positive skin vasculitis, and concomitant combined thrombophilia.

Clinical picture, outcomes and predictors of relapse in eosinophilia-associated coronary vasospasm: data from a European multicentric study

Abstract Background and aims Eosinophilia-associated coronary vasospasm is an under-recognized and scarcely reported life-threatening condition for whose management is undefined. Preliminary data suggest that eosinophil-targeted therapies could be beneficial. Our aim is to provide an in-depth report of the clinical picture, outcomes and predictors of relapse in patients with eosinophilia-associated coronary vasospasm. Methods European multicentric retrospective study, gathering twenty centers across France, Italy and Spain. Patients of 15 years or more with definite or suspected coronary vasospasm according to the 2017 International standardization of diagnostic criteria for vasospastic and concomitant (± 48 hours) eosinophilia (threshold: 0.5 x 109/L) were included in this study. Outcomes included vasospasm relapse and other major cardiovascular events (MACE) during follow-up. Predictors of relapse were assessed using bidirectional stepwise regression analysis. Results Thirty-seven patients (median age: 52 [42-64] years, 43% women) were included, among which 16 (43%) had aspirin-exacerbated respiratory disease, 16 (43%) and 13 (35%) fulfilled classification criteria for Eosinophilic Granulomatosis with Polyangiitis (all with negative antineutrophil cytoplasmic antibodies) and Hypereosinophilic syndrome, respectively. There was no predominant coronary territory involved. A iatrogenic trigger was evidenced in 7 (19%) patients, consisting in all cases but one of non-steroidal anti-inflammatory drugs. After a median follow-up of 32 [12-63] months, 20 (54%) patients relapsed (median time to first relapse: 10 [5−29] months), despite vasodilators regimen in 95% of cases. Besides coronary vasospasm(s), 13 (35%) patients experienced an additional MACE. In multivariate analysis, persistent eosinophilia (i.e. absolute eosinophil count > 0.5 x 109/L at the time of coronary vasospasm relapse or at last follow-up for relapsing and non-relapsing patients respectively) was the sole indepedendent predictor of relapse (Odds Ratio 8.87 [3.28-24.82]; p<0.001). All six patients treated with interleukin-5 biologics remained relapse-free under treatment. Conclusions Eosinophilia-associated coronary vasospasm can occur in patients with type 2 inflammation. Long-term normalization of absolute eosinophil counts appears crucial in preventing the recurrence of eosinophilia-associated coronary vasospasm, while conventional use of vasodilators seems ineficient.

18F-FDG PET/CT in the Evaluation of Polyarteritis Nodosa.

A 61-year-old man with a medical history of human immunodeficiency virus well controlled on antiretroviral therapy presented for distal sensorimotor symptoms, fatigue, and recurrent fevers. Erythrocyte sedimentation rate and C-reactive protein were both elevated. Antineutrophilic cytoplasmic antibody and antinuclear antibodies were negative. Neurologic imaging workup was unremarkable. 18F-FDG PET/CT, which was crucial for diagnosis, demonstrated pathological tracer activity throughout the medium-sized vessels with sparing of the aorta. In view of presentation, comorbidities, and imaging findings, polyarteritis nodosa was diagnosed. The patient was treated appropriately with steroids and cyclophosphamide with significant symptomatic improvement.

Clinical associations with thyroid disease in ANCA-associated vasculitis.

To evaluate the frequency and the clinical relevance of thyroid disease in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) patients. A total of 305 AAV patients admitted to the Second Affiliated Hospital of Chongqing Medical University between October 2010 and December 2023 were analyzed. Demographic, clinical, and laboratory data were compared between AAV patients with and without thyroid disease. Univariate and multivariate logistic regression analyses were conducted to identify factors associated with thyroid disease in AAV patients. Among the 305 AAV patients, 52 (17.0%) had concurrent thyroid disease. In univariate analysis, gender, coronary artery disease, renal involvement, anti-Ro/SSA antibodies, anti-Ro52 antibodies, anti-thyroglobulin antibodies (TgAb), and anti-thyroid peroxidase antibodies (TPOAb) exhibited significant differences between AAV patients with and without thyroid disease (P < 0.05). Multivariate analysis revealed that female gender (odds ratio (OR) = 2.423, 95% confidence interval (95% CI) 1.241, 4.729; P = 0.009), concurrent coronary artery disease (OR = 2.998, 95% CI 1.280, 7.019; P = 0.011), and positive anti-Ro/SSA antibodies (OR = 4.697, 95% CI 1.960, 11.257; P = 0.001) were associated with thyroid disease in AAV patients. AAV patients have a higher incidence of thyroid disease. Regular monitoring of thyroid function is advised for AAV patients, particularly for women, those with coronary artery disease, and those who are positive for anti-Ro/SSA antibodies. Key Points • AAV patients have a higher incidence of thyroid disease. • The potential clinical relevance of AAV patients with thyroid disease was explored. • Regular monitoring of thyroid function is advised for AAV patients.

Granulomatosis with polyangiitis with lacrimal gland enlargement and pancreatic swelling: case report and literature review.

A 62-year-old man had bilateral eyelid swelling for 4 months. Two months before admission, he developed fatigue and lost 5 kg of bodyweight. Further examination revealed elevated serum C-reactive protein, normal angiotensin-converting enzyme, elevated proteinase-3 antineutrophil cytoplasmic antibody (PR3-ANCA), and normal IgG4 concentration. Chest X-ray and computed tomography showed no enlarged hilar lymph nodes, but positron emission tomography-computed tomography showed fluorodeoxyglucose accumulation in both lacrimal glands, in lung nodules, and in the pancreas. Tissue biopsies of the lacrimal glands and pulmonary nodules showed granuloma with giant cells, but no IgG4-positive cells or fibrosis. Pancreatic tissue showed no findings of autoimmune pancreatitis. In the 2022 ACR/EULAR classification criteria for granulomatosis with polyangiitis, the total score was 10 points. Final comprehensive diagnosis was granulomatosis with polyangiitis, based on the negative results of differential diseases, such as IgG4-related diseases and sarcoidosis. Prednisolone 60 mg/day was started on day 8, and rituximab 500 mg/body/week on day 12. After beginning treatment, general malaise and lacrimal gland enlargement were resolved, PR3-ANCA and C-reactive protein became negative, and the nodular shadow in the lungs disappeared. This is the first report of granulomatosis with polyangiitis presenting both lacrimal gland and pancreatic lesions.

New Drug: Avacopan for antineutrophil cytoplasmic antibody–associated vasculitis

New Drug: Avacopan for antineutrophil cytoplasmic antibody–associated vasculitis

Defects in B-lymphopoiesis and B-cell maturation underlie prolonged B-cell depletion in ANCA-associated vasculitis

ObjectivesB-cell depletion time after rituximab (RTX) treatment is prolonged in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) compared with other autoimmune diseases. We investigated central and peripheral B-cell development to identify...

Steroid-sparing strategy for the treatment of vasculitis associated with antineutrophil cytoplasmic antibodies

Glucocorticoids (GC) and immunosuppressants (IS) are traditional treatments for vasculitis associated with antineutrophil cytoplasmic antibodies (ANCA), often resulting in the development of infections, diabetes mellitus and other adverse events (AEs). The development of a steroid-sparing strategy using biologic disease-modifying antirheumatic drugs (bDMARDs, including rituximab, etc.) and synthetic targeted drugs (avacopan) has radically improved the course of the disease. Currently, there are increasing number of basic and clinical trials of numerous bDMARDs that effectively reduce the number of AEs associated with GC and IS. The steroid-sparing therapeutic strategy not only shows considerable efficacy, but also opens up new perspectives for the treatment of patients with ANCA-associated systemic vasculitis.

Intractable otitis media-Pathogenesis and treatment of Eosinophilic otitis media (EOM) and otitis media with Antineutrophil cytoplasmic antibody (ANCA) -associated vasculitis (OMAAV)

Intractable otitis media-Pathogenesis and treatment of Eosinophilic otitis media (EOM) and otitis media with Antineutrophil cytoplasmic antibody (ANCA) -associated vasculitis (OMAAV)

Anti-Neutrophil Cytoplasmic Antibody (ANCA)-Associated Fasciitis Mimicking Pseudogout in an Older Patient: A Diagnostic Challenge and Treatment Approach

Anti-Neutrophil Cytoplasmic Antibody (ANCA)-Associated Fasciitis Mimicking Pseudogout in an Older Patient: A Diagnostic Challenge and Treatment Approach

ANCA-Negative Pauci-Immune Glomerulonephritis: A Review.

Pauci-immune glomerulonephritis (PIGN) is typically secondary to antineutrophil cytoplasmic antibodies (ANCA) small-vessel vasculitis. However, some cases lack detectable circulating ANCA and are called ANCA-negative PIGN (seronegative PIGN). The reported incidence of this varies greatly. Its relationship to ANCA-associated vasculitis (AAV) is unclear. This review explores the pathophysiology of seronegative PIGN and summarizes findings from 12 studies focusing on this disease. The role of neutrophils appears to be central, with activation through cellular and humoral mechanisms. Most studies have noted less extrarenal involvement and more chronic changes in the kidney biopsy in seronegative PIGN compared to ANCA-positive cases. Studies have mostly reported using corticosteroids with cyclophosphamide for induction therapy and azathioprine for maintenance. The renal survival was noted to be lower compared to ANCA-positive PIGN. Whether ANCA-negative PIGN represents a distinct disease or is part of the AAV spectrum remains unclear. Prospective large-scale studies are needed to understand this disease for optimal diagnosis and management.

The uncertain correlation of ANCAs in patients with lupus nephritis and crescents, an experience from Chinese centers.

The precise role of anti-neutrophil cytoplasmic antibodies (ANCAs) in the pathologic course of crescentic lupus nephritis (LN) remains unclear. Our study aimed to assess whether ANCA-positive serology in patients with LN and crescents is associated with different clinicopathologic features and outcomes. We reviewed the records of 658 patients diagnosed with LN between 2010 and 2022. Among them, 64 (9.7%) patients who had complete follow-up and clinical data were reclassified as crescentic glomerulonephritis. Of these, 11 patients with incomplete ANCA data and 7 patients with less than 10 glomeruli under light microscopy were excluded; ultimately, 46 patients were enrolled: 12 with ANCA positivity and 34 with ANCA negativity. Clinicopathological characteristics and outcomes were analysed and compared. Our data did not reveal any differences in clinical or laboratory parameters or histopathological features except for a significantly higher level of proteinuria or proportion of nephrotic syndrome (p < 0.05) at presentation before biopsy in the ANCA-negative group than in the ANCA-positive group,and a lower level of serum albumin (p < 0.05) in the ANCA-negative group than in the ANCA-positive group. No significant differences in complete remission or partial response were detected between the two groups based on the 2021 KDIGO criterion. Short-term follow-up (average follow-up time of less than 3 years) did not reveal any difference in outcomes between ANCA-positive and ANCA-negative crescentic LN. However, the role of ANCAs in the pathological course of crescentic lupus nephropathy and the effect of ANCAs on long-term outcomes remain to be determined.

Comparison of different ANCA detection methods in a predominantly MPO-ANCA-associated vasculitis cohort

We compared different antineutrophil cytoplasmic antibody (ANCA) detection methods using a predominantly myeloperoxidase (MPO)-ANCA-associated vasculitis cohort. Stored sera from 147 patients with untreated ANCA-associated vasculitis (AAV), including microscopic polyangiitis and granulomatosis with polyangiitis (n = 115 and 32, respectively), and 124 disease controls were tested for P-ANCA and C-ANCA with immunofluorescence (IIF), and for MPO-ANCA and proteinase 3 (PR3)-ANCA with different antigen-specific immunoassays: direct enzyme-linked immunosorbent assay (ELISA), chemiluminescent enzyme immunoassay (CLEIA), third-generation fluorescent enzyme immunoassay (FEIA), and latex turbidimetrical immunoassay (LTIA). In addition, MPO-ANCA and PR3-ANCA titers were calibrated using certified reference materials (CRMs). The sensitivities and specificities for AAV diagnoses were 95% and 94% (IIF), 86% and 98% (ELISA), 93% and 94% (CLEIA), 92% and 96% (FEIA), and 68% and 88% (LTIA). Dual IIF/antigen-specific immunoassay testing reduced diagnostic accuracies from 94% to 93%. The quantitative agreement between ANCA levels measured using CLEIA and FEIA and calibrated using CRMs was not good. In conclusion, this study demonstrated the high performance of antigen-specific immunoassays for AAV diagnosis in a predominantly MPO-ANCA-associated vasculitis cohort and suggested that the benefit of dual IIF/antigen-specific immunoassay testing is limited. Standardizing ANCA measurements using different immunoassays was difficult, even when using CRMs.

Assessing Clinical Outcomes and Treatment Efficacy in a Patient with Crescentic Glomerulonephritis (CGN)- A Case Report

Crescentic glomerulonephritis (CGN) is a rapidly progressive renal condition marked by crescent formation in the glomeruli, often resulting in end-stage renal disease (ESRD) if not promptly addressed. This case report examines a 54-year-old female with a sudden onset of generalized edema and reduced urine output, which led to her hospitalization. Laboratory evaluations revealed acute renal failure with markedly elevated serum creatinine levels. Despite a background of Antineutrophil Cytoplasmic Antibodies (ANCA)-associated vasculitis, her management was complicated by inconsistent adherence to immunosuppressive therapy. Notably, severe hypertension exacerbated her renal impairment, necessitating immediate intervention. The clinical progression of CGN highlights the critical importance of early diagnosis, continuous monitoring, and a multidisciplinary approach for effective management. Emphasizing patient education and lifestyle modifications, particularly in dietary habits and blood pressure control, can significantly influence treatment outcomes. This case illustrates the urgency of addressing CGN and the necessity of a collaborative healthcare strategy to improve prognosis and enhance the patient's quality of life.

Long-term efficacy of mepolizumab in patients with eosinophilic granulomatosis with polyangiitis: a propensity score matching analysis in the multicenter REVEAL cohort study.

Mepolizumab (MPZ) has demonstrated efficacy in clinical trials for eosinophilic granulomatosis with polyangiitis (EGPA); however, few studies compare the disease course between patients treated with MPZ (MPZ group) and those who were not treated with MPZ (non-MPZ group) in real-world settings. This study aimed to compare the disease course and outcomes between the two groups and assess the long-term efficacy of MPZ in a multicenter cohort in Japan. Methods: We enrolled 113 EGPA patients registered in the cohort until June 2023. Data on clinical characteristics, disease activity, organ damage, treatments, and outcomes were retrospectively collected. To minimize potential confounding factors, we conducted propensity score matching (PSM). After PSM, 37 pairs of matched patients were identified. Clinical characteristics, including age at disease onset, sex, disease duration at last observation, antineutrophil cytoplasmic antibody positivity at disease onset, Birmingham Vasculitis Activity Score (BVAS) at disease onset, and Five-factor score at disease onset, were comparable between the groups. The median BVAS at the last observation was 0 in both groups; however, more cases in the non-MPZ group exhibited elevated BVAS, resulting in a significantly higher BVAS in the non-MPZ group at the last observation (median; MPZ group: 0, non-MPZ group: 0, p=0.028). The MPZ group had significantly lower glucocorticoid (GC) doses at the last observation (median; MPZ group: 4 mg/day, non-MPZ group: 5 mg/day, p=0.011), with a higher proportion achieving a GC dose ≤ 4 mg/day at the last observation (MPZ group: 51.4%, non-MPZ group: 24.2%, p=0.027). Three models of multivariable logistic regression analyses were performed to identify factors associated with GC doses ≤ 4 mg/day at the last observation. In all models, achieving a GC dose ≤ 4 mg/day was positively associated with MPZ administration and inversely associated with asthma at disease onset. Finally, we evaluated the survival rates between the groups, and the 5-year survival rates were significantly higher in the MPZ group compared to the non-MPZ group (MPZ group: 100%, non-MPZ group: 81.3%, p=0.012). Mepolizumab not only contributes to disease activity control but also reduces the GC dose, which may lead to improved survival in EGPA patients.

Characteristics of Severe Asthma Clinic Patients With Eosinophilic Granulomatosis With Polyangiitis

BackgroundEosinophilic granulomatosis with polyangiitis (EGPA) is a rare form of anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis associated with varying clinical presentations and overlapping multiorgan involvement. Asthma is a predominant feature of EGPA, typically in its prodromal phase, often severe and precedes vasculitic complications. However, there is paucity of studies describing the prevalence and characteristics of EGPA in the asthma population. ObjectiveWe aim to describe the clinical and serological characteristics and longitudinal therapeutic outcomes of patients with EGPA in the severe asthma (SA) cohort. MethodsRetrospective study of patients with EGPA attending the multidisciplinary SA clinic in a tertiary hospital from 2011 to 2023 was conducted. Baseline demographics, organ manifestations, biological markers, lung function and therapeutic outcomes were assessed. Results23 out of 596 patients in the SA registry were identified to have EGPA. Median time interval between asthma and EGPA diagnosis was 10 years (range 2.5 to 32 years). Almost all patients (95.7%) had peak blood eosinophil count of >1.0 x 109/L (range 0.47 – 14.08 x 109/L). Upper airway involvement was the most detected manifestation in addition to asthma, followed by neuropathy and renal involvement. Patients who were treated with biologic therapy were significantly younger, had more upper airway, renal, pulmonary involvement and lower five factor score (FFS). ConclusionThe prevalence of EGPA in the SA population was 3.9% in our cohort. Its diagnosis requires high clinical suspicion in patients with SA and blood eosinophilia, prompting stringent evaluation for extrapulmonary manifestations and multidisciplinary involvement.

Hydralazine-Associated Anti-neutrophilic Cytoplasmic Antibody (ANCA)-Associated Vasculitis: A Model of Drug-Associated Autoimmunity

Hydralazine-Associated Anti-neutrophilic Cytoplasmic Antibody (ANCA)-Associated Vasculitis: A Model of Drug-Associated Autoimmunity