Histological and immunological features of non-eosinophilic nasal polyps

OBJECTIVE: The aim of this study was to investigate the histoimmunological features of non-eosinophilic nasal polyps (NPs). METHODS: Thirty patients with chronic rhinosinusitis and NPs were included in this study. NPs were grouped into eosinophilic and non-eosinophilic types according to the amount of eosinophils in the NPs. The amount of serum total IgE and peripheral blood eosinophils were measured. Basement membrane (BM) thickness was measured, along with the expression of chemokine receptor 5 (CCR5) and chemokine receptor 3 (CCR3) in NP lymphocytes. RESULTS: Non-eosinophilic NPs comprised 66.7% of the total NPs included in this study. The amount of eosinophils in NPs was related to eosinophilia of the peripheral blood, but not to elevated serum IgE. BM was significantly thinner in non-eosinophilic than in eosinophilic NPs. Lymphocytes expressing CCR5 or CCR3 were less frequently found in non-eosinophilic than in eosinophilic NPs. CONCLUSION: Histoimmunological characteristics of non-eosinophilic NPs differ from those of eosinophilic NPs; non-eosinophilic NPs may be featured by thinner BM and fewer CCR5- and CCR3-positive lymphocytes. (c) 2007 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.