Sensibilização alérgica em brasileiros com dermatite atópica : comparação entre os perfis de sensibilização a componentes alergênicos em diferentes fenótipos

• Ano de defesa: 2017
• Autor(a) principal: Oliveira, Lucila Camargo Lopes de [UNIFESP]
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de São Paulo (UNIFESP)
• Palavras-chave em Português: Hypersensitivity; Immunoglobulin E; Atopic dermatitis; Food hypersensitivity; Tropomiosin; Hipersensibilidade; Imunoglobulina E; Dermatite atópica; Hipersensibilidade alimentar; Tropomiosina
• Link de acesso: https://sucupira.capes.gov.br/sucupira/public/consultas/coleta/trabalhoConclusao/viewTrabalhoConclusao.jsf?popup=true&id_trabalho=5201299; http://repositorio.unifesp.br/handle/11600/50392

Background: atopic dermatites (AD), the most common cutaneous inflammatory disease and prime manifestation of atopic march, it is mostly IgE-mediated. It is estimated that, in one third of moderate to severe cases, food allergens are involved. In the latest years, the development of molecular allergy has brought a better understanding of the sensitization process and favored the establishment of more precise diagnosis and prognosis. Until now molecular studies with AD patients are scarces. Objectives: (1) analyze the sensitization profile (focusing on food allergens) of different severity of AD by the measurement of specific IgE towards allergens (ImmunoCAP®) and its components on a microarrayed-based platform (ImmunoCAP-ISAC®); (2) compare ImmunoCAP® and ImmunoCAP-ISAC® results; (3) identify cross-reactive components for the studied population. Methods: a cross-sectional study on a tertiary allergy service in São Paulo, Brazil. Patients with non-severe AD (SCORAD<50), severe AD (SCORAD≥50) and suspected for IgE-mediated food allergy without AD had their sensitization profile determined by ImmunoCAP® (white hen’s egg, cow’s milk, alpha-lactalbumin, beta-lactoglobulin, casein, fish, peanut, soy, wheat, dog’s epithelium, cat’s epithelium, Blomia tropicalis, Dermatophagoides pteronyssinus, Blatella germanica and Periplaneta Americana, fx2- seafood mix- and mx2- fungus mix- and ImmunoCAP-ISAC® besides the measurement of total IgE. Results: 76 patients took part in the study (non-severe AD, n=29; severe AD, n=30; suspected IgE-mediated food allergy, n=14- 3 patients with eosinophilic esophagitis were withdrawn). The severe AD group showed significantly higher total IgE levels (>5000 vs 791 vs 939,5 kU/l, severe AD, non-severe AD and suspected food allergics, respectively) and sensitization to a broader number of ImmunoCAP® allergens. Molecular analysis revealed association between severe AD and nPen m1 sensitization (46,7% vs 13,8% of non-severe AD). Moderate positive correlation (0,523 to 0,684) were observed to dog’s epithelium ImmunoCAP® and rCan f 1, Blomia tropicalis ImmunoCAP® and rBlo t 5, CAPfx2 and nPen m 1, alpha-lactalbumin ImmunoCAP® and nBos d 4, beta-lactoglobulin ImmunoCAP® and nBos d 5 and casein ImmunoCAP® and n Bos d 8. Correlations between cat’s epithelium ImmunoCAP® and rFel d 1, Dermatophagoides pteronyssinus (Dp) and nDer p 1 and Dp and rDer p 2 were stronger (0,701 to 0,741). Shrimp and house-dust mite tropomyosin and cat serum albumin were the cross-reactive componentes with higher sensitization rates (30% and 13,7%, respectively). Conclusions: in general, severe AD patients were sensitized more often to food allergens compared to non-severe AD patients. There were no difference between the two groups for ImmunoCAP® inhalant allergens. However, molecular analysis showed significantly higher sensitization rates to Blo t 5 and nPen m 1. ImmunoCAP® and ImmunoCAP-ISAC® do not have comparable results. At the present studied population cross-reactive components with higher sensitization rates were tropomyosins and serum albumins.