Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 10 3 2011 09 15 221 226 EN Monireh Mokhtari Amirmajdi Department of Medical Mycoparasitology, Mashhad University of Medical Sciences, Mashhad, Iran Nemat Allah Mokhtari Amirmajdi Department of Otolaryngology, Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad, Iran Iman Eftekharzadeh Mashhadi Department of Medical Mycoparasitology, Mashhad University of Medical Sciences, Mashhad, Iran Farahzad Jabari Azad Bu Ali Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran Jalil Tavakol Afshari Bu Ali Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran Mohammad-Taghi Shakeri Department of Biostatic, Mashhad University of Medical Sciences, Mashhad, Iran 2015 10 01 Inhalation of fungal spores is shown to participate in the development of allergic rhinitis symptoms. In this study, relation between presence of Alternaria in the human nasal cavity and allergic rhinitis is assessed. In a case-control study, 58 allergic rhinitis patients were compared with a well-matched control group of fifty healthy volunteers for sensitization to Alternaria (by skin prick test) and detection of Alternaria in their nasal mucous by conventional methods (microscopy with Methylene Blue stain and culture in Sabourad dextrose agar). Severity of the disease was determined according to  the ARIA classification. Pearson chi-square test was applied to compare the proportional difference between the study groups for detection of Alternaria in the nasal cavity, and sensitization to Alternaria. Relation between detection of Alternaria and allergic rhinitis was significant [OR = 18.18 (4.02-82.50)] In addition, sensitization to Alternaria showed a significant relation with the disease [OR  =  2.8 (2.1-3.8)]. There  was a significant relation between the  presence  of Alternaria in the nasal cavity and sensitization to Alternaria [OR =  10.4 (3.8-28.3)]. Both sensitization to  Alternaria and presence of Alternaria in the nasal cavity did not  have a significant relation with the severity of allergic rhinitis. This study suggests Alternaria as a major  allergen that  its  presence  in  the  nasal  cavity and  subsequent  development  of sensitization have significant role in the induction of allergic rhinitis. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/313 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/313/313