RESUMO
BACKGROUND: Allergic rhinitis is an IgE-mediated inflammatory disease of the nasal mucosa, which is usually diagnosed by typical symptoms, positive skin tests, and/or serum specific IgE antibodies to allergens. Despite suggestive symptoms of allergic rhinitis, some patients have a negative diagnostic test for atopy. OBJECTIVE: To evaluate in the nose the inflammatory response, specific IgE to Dermatophagoides pteronyssinus (DP), and the response to a nasal allergen provocation test with DP (NAPT-DP), in patients with persistent nonallergic rhinitis (PNAR) compared with patients with persistent allergic rhinitis (PAR) and healthy controls. METHODS: Fifty patients with PNAR, 30 with PAR to DP, and 30 healthy controls were studied by determining the nasal leukocyte-lymphocyte phenotype by flow cytometry (CD16, CD8, CD4, CD33, CD3, and CD45), nasal eosinophil cationic protein (ECP), albumin, total and specific IgE to DP, and NAPT-DP. RESULTS: The PNAR patients showed a similar leukocyte-lymphocyte phenotype in nasal lavage to the PAR patients and was different to the healthy controls. Within the PNAR group, 54% showed a positive NAPT-DP, with 22% of these having nasal specific IgE to DP. CONCLUSION: These data support the hypothesis that in persistent nonallergic rhinitis some patients may have local inflammation, nasal IgE production, and a positive response to a nasal allergen provocation test despite no evidence of systemic atopy. Further research is needed to evaluate the influence of other perennial allergens and/or immunologic mechanisms. CLINICAL IMPLICATIONS: The local production of IgE antibodies without systemic detection is a condition that should be considered in patients with PNAR.
