Inflammatory cell and epithelial characteristics of perennial allergic and nonallergic rhinitis with a symptom history of 1 to 3 years' duration

Background: Perennial rhinitis is an inflammatory condition of the mucosal lining of the nose that may be caused by allergic and nonallergic mechanisms. Objective: We sought to characterize the cellular pattern and structural changes in the nasal mucous membrane of patients with perennial rhinitis and compare them with those of control subjects. Methods: Biopsy specimens were obtained from 27 patients with perennial allergic rhinitis (PAR), from 12 patients with perennial nonallergic rhinitis (PNAR) with eosinophils present an the nasal smear, and from 6 control subjects without rhinitis. In 10 of 27 patients with PAR who were also allergic to pollen, biopsy specimens were taken within the respective season (PAR(season)). In the other 17 patients, the biopsy was taken outside the pollen season (PAR(outside season)). Inflammatory cells were identified by using mAbs to their unique granular proteins. Results: The characteristic feature of perennial rhinitis was the accumulation of activated (degranulated) mast cells and eosinophils in the nasal mucosa. The tissue cosinophil/meutrophil ratio was higher, and the loss of epithelial integrity was greater in all patient groups compared with the control subjects. The extent of epithelial damage was significantly larger in patients in the PAR(season) group compared with that in the PAR(outside season) and PNAR groups, which did not significantly differ from each other in this respect. The number of eosinophils and mast cells was higher in the PNAR group compared with the PAR groups. In all patient groups, the number of eosinophils correlated with the loss of epithelial integrity. The number of mast cells did not correlate with the extent of epithelial damage nor did the number of neutrophils, except in patients in the PAR(season) group. Conclusion: The accumulation of eosinophils and mast cells, as well as loss of epithelial integrity, was characteristic for perennial rhinitis. Loss of epithelial integrity in the nasal mucosa map be a consequence of the activity of accumulated eosinophils.