Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 4 4 2005 12 15 193 195 Mohammad Javad Ashraf Negar Azarpira Mehrzad Pourjafar Bijan Khademi 2015 10 01 We present a case of allergic fungal sinusitis (AFB) in a 20-year old man with few months' history of bilateral nasal obstruction and discharge with unilateral proptosis that underwent maxillary antrostomy due to the mass in paranasal sinuses. Histological examination of tissue showed branching fungal hyphae interspersed with allergic mucin without fungal invasion to soft tissue. The patient received local steroid for 4 months and had no problem during follow up. Fungal culture was performed and Bipolaris fungus grew. Although most dematiaceous fungal infections occur in immunocompetent patients, the incorrect diagnosis and insufficient treatment may be life threatening. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/122 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/122/122