Background:Eosinophilic granulomatosis with polyangiitis (EGPA), previously known as Churg-Strauss syndrome, is a systemic disease characterized by late onset asthma associated with small- and/or medium-size vessel vasculitis, besides eosinophil-mediated cytotoxic organ damage. About 20-30% of patients with EGPA displays allergic manifestations related with inhalant sensitization, while prevalence of food and drug allergy is unknown in this context. Moreover, some authors in the past hypothesized in favor of a possible role of allergen-specific immunotherapy (ASIT) as a trigger of disease.Objectives:Aim of the present study is to establish the prevalence of each category allergen sensitization and to determine whether atopy or specific immunotherapy could influence clinical expression of the disease.Methods:Our study consisted in a retrospective demographic and clinical data collection regarding EGPA history (including age at diagnosis, organ and tissue involvement, autoantibody profile) and the presence of allergic comorbidities or previous drug hypersensitivity reactions. Patients without either proven allergic reactions or positive tests have been excluded.Results:Fifty-three (53) patients with definitive diagnosis of EGPA have been included in the analysis among which 25 (47.2%) with chronic respiratory allergy or previous acute allergic reaction. Among allergic patients 15 (60%) resulted sensitized towards inhalants and among them 13 (86.7%) displayed multiple sensitization. Drug allergy affected 13 patients (52%), food 4 (16%). Among 15 patients with respiratory allergy, 13 were eligible to allergen-specific immunotherapy (ASIT). Seven (7) subjects underwent ASIT prior EGPA diagnosis with an average time-to-EGPA of 16.2 years. No statistically significant difference was found in terms of sex, age at diagnosis, positivity for or specificity of anti-neutrophil cytoplasm antibodies (ANCA), eosinophil count at onset, pattern of clinical manifestations comparing allergic vs. non-allergic, ASIT vs. non-ASIT, ASIT vs. allergic, ASIT vs. eligible.Conclusion:Among patients with EGPA allergies are highly prevalent, particularly towards inhalants and drugs. In the great majority of patients multiple sensitization profile is found. Atopy doesn’t seem to be associated with specific patterns of disease presentation. The absence of correlation between inhalant ASIT exposure and variation in mode and time of EGPA onset doesn’t support the hypothesis of a its potential role in triggering the disease.References:[1]Berti A et al. Severe/uncontrolled asthma and overall survival in atopic patients with eosinophilic granulomatosis with polyangiitis. Respiratory Medicine 2018; DOI: 10.1016/j.rmed.2018.07.017[2]Cottin V et al. Respiratory manifestations of eosinophilic granulomatosis with polyangiitis (Churg–Strauss). European Respiratory Journal 2016; DOI: 10.1183/13993003.00097-2016Disclosure of Interests:Luca Moroni: None declared, adriana cariddi: None declared, Silvia Sartorelli: None declared, Emanuel Della Torre: None declared, Tommaso Germanò: None declared, Giuseppe Alvise Ramirez: None declared, Enrica Bozzolo: None declared, Mona-Rita Yacoub: None declared, Lorenzo Dagna Grant/research support from: The Unit of Immunology, Rheumatology, Allergy and Rare Diseases (UnIRAR) received unresctricted research/educational grants from Abbvie, Bristol-Myers Squibb, Celgene, Janssen, Merk Sharp & Dohme, Mundipharma Pharmaceuticals, Novartis, Pfizer, Roche, Sanofi-Genzyme, and SOBI., Consultant of: Prof Lorenzo Dagna received consultation honoraria from Abbvie, Amgen, Biogen, Bristol-Myers Squibb, Celltrion, Novartis, Pfizer, Roche, Sanofi-Genzyme, and SOBI.
Optimization of the basophil activation test in the diagnosis and qualification for treatment by means of allergen-specific immunotherapy in children with respiratory allergy to house dust mites
