The Role of Fungus in Rhinosinusitis: Epidemiology, Mycology, Immunology and Pathogenesis, Criteria For Categorization, Laboratory Diagnosis, The Role of Antifungals in Treatment

Fungi found ubiquitously in internal and external air and the environment, may commensally present in human respiratory system but also involves in invasive and non-invasive rhinosinusitis. Fungal genera reported as aetiologic agents include predominantly Aspergillus, Pseudallescheria, and dematiaceous taxa like Bipolaris, Drechslera, Stemphylium and Chaetomium. These fungi cause an allergic reaction and may trigger an eosinophylic infiltration in nasal tissue. This paper, reviews new concepts and concensus criteria and categorization of fungal rhinosinusitis as acute invasive, chronic invasive, fungus ball and allergic fungal rhinosinusitis based on the immunologic relationship between the host and fungus, mycology and laboratory identification of fungi causing rhinosinusitis, and different treatment proposals according to the four categories.