Enhancement of submicroscopic damage of the nasal epithelium by topical allergen challenge in patients with perennial nasal allergy

The purposes of this study were to clarify whether damage of the nasal epit helium exists in patients with nasal allergy, and how the morphology of the epithelium changes after topical allergen challenge. Electron microscopy r evealed 2 characteristic features in the nasal epithelium of patients with perennial nasal allergy - an increase in the number of epithelial cells wit h cytoplasmic vacuoles, and markedly widened intercellular spaces - althoug h these changes were unclear under light microscopy. The density of vacuola ted cells significantly increased 24 hours after allergen challenge. Furthe r, the number of eosinophils that were associated with vacuolated cells was significantly higher in patients with nasal allergy than in controls. Thes e morphological changes, thus, were considered to be types of damage to the nasal epithelium associated with nasal allergy Such changes may be among t he causes of nasal hyperreactivity, which is an important feature of nasal allergy.