Background: Nonallergic rhinitis comprises many subgroups of rhinitis (vasomotor rhinitis, nonallergic rhinitis with eosinophilia syndrome, occupational rhinitis, idiopathic rhinitis, etc. in which its main feature is known to be free of allergy. We evaluate the cellular infiltrate of subjects with idiopathic rhinitis and compare them with allergic and control counterparts for detecting underlying pathophysiology.
Methods: Subjects selected from patients admitted to Istanbul University Medical Faculty between 2006 and 2009 were classified into idiopathic rhinitis (n = 16; mean age, 26.5 years), allergic rhinitis (n = 17; mean age, 31.1 years), and the control (n = 25, mean age, 28.8 years) groups. Inferior turbinate specimens were collected using Gerritsma forceps. Skin-prick testing was performed. Immunohistochemical detection was performed using B7 (chymase, clone CC1) and G3 (tryptase, clone AA1) primary antibodies for mast cells, human eosinophil major basic protein (clone BMK-13) for eosinophils, and immunoglobulin E (IgE) Ab-1 for mast and plasma cells in epithelium, superficial, and deep submucosa.
Results: We found significantly higher levels of mast cells within the different sites of nasal mucosa of allergic and idiopathic subjects compared with normal mucosa (p < 0.05). Additionally, a significant increase was observed in IgE(+) cells of the patients with allergic and idiopathic rhinitis compared with the controls (p < 0.05 for each) Eosinophils were significantly increased within the epithelium of allergic patients' mucosa.
Conclusion: We seem to have supportive data about possible mechanisms of "idiopathic rhinitis" that suggests local allergic inflammation. The study results provided important information for further provocation and immunohistochemical studies analyzing the shared mechanism of allergic and idiopathic rhinitis.