Vol.98 No.5 contentsPRACTICA OTO-RHINO-LARYNGOLOGICA
Vol. 98 No. 5 May 2005
Multifactorial Processes in the Development
and Persistence of Chronic Sinusitis
Sachio Takeno and Koji Yajin
(Hiroshima University)
In the past decades, a great deal of knowledge has been accumulated about the immunopathology of chronic sinusitis. Introduction of the endoscopic approach and low-dose macrolide therapy to the clinical field facilitated recognition of the significance of impairment of two important mechanisms necessary for healthy sinus function: patency of sinus ostia in the lateral nasal wall and the maintenance of mucociliary clearance, in the development of the sinus disease. The division of chronic sinusitis into allergy-associated and non-allergy associated highlights the heterogenicity in the celluar profile and cytokine expression involved in the sinus mucosa. Recent studies have implicated eosinophils as a central player in persistent inflammation occurring in non-infectious chronic sinusitis. High expression of Th2-type cytokines concomitant with the infiltration of a predominant number of CD4-positive cells and itsTh2 subsets play a role in the pathogenesis of eosinophil inflammation. In addition, the finding that part of the non-allergic patients also shared Th-2 type immune responses supports the concept of chronic sinusitis as a Th2-mediated disease process.
Despite these achievements, management and treatment of chronic sinusitis with typical eosinophilia remain difficult and frustrating work for ENT surgeons. Corticosteroids and leukotriene receptor antagonists are potent anti-inflammatory agents available for symptomatic relief and prevention of the disease after sinus surgery. Emerging views on the molecular biologic action of both glucocorticoid and cysteinyl leukotriene receptors elucidate complex interplay between cytokines, chemical mediators, and inflammatory products in inducing eosinophil accumulation in the sinus mucosa.
Key words : chronic sinusitis, allergic rhinitis, cytokines, eosinophils, steroid therapy