fa پژوهشي اصیل Original Research <strong>Background and Objectives:</strong> To determine the association of hyper-reactivity to environmental allergens&nbsp;and mucosal secretion cytology with the course of disease in patients with chronic rhinosinusitis and nasal&nbsp;polyps (CRSwNP).<br> <strong>Methods:</strong> A cross sectional study was conducted at Tehran Clinic of Asthma and Allergy in 2016. Adult patients&nbsp;who earned the definite diagnosis of CRSwNP and were free of serious underlying disease were selected.<br> A comprehensive history regarding the course of disease was taken. Success or failure of previous interventions&nbsp;was defined as subsiding the symptoms and no need for further invasive intervention of surgery. Physical examination,&nbsp;pulmonary function test, nasal smear from both nasal cavities and skin prick test were performed for all&nbsp;enrolled subjects. The results were compared among participants with different course of disease.<br> <strong>Results:</strong> A total of 45 patients with mean age of 35.8&plusmn;11.7 (18 to 60 years) were enrolled. Of the participants,&nbsp;30 (66.7%) had asthma, medical treatment was failed in 23(51.1%), 25 underwent surgery in whom it was&nbsp;failed in 5 (11.1%). Regardless of course of disease, neutrophilia was the predominant cytology of nasal smear.&nbsp;Of the participants, 17 (37.8%) had no sensitization, while, 11(24.4%) showed mono-sensitization and<br> 17(37.8%) were poly-sensitized. Seasonal allergy was found in 16(35.5%), while, perennial sensitization was in&nbsp;19 (42.2%). Failures of medical treatment were more sensitized to seasonal allergens (45.2% vs 14.3%,&nbsp;p=0.045). Failures of surgery, were found to have poly sensitization to both of perennial and seasonal allergens&nbsp;(66.7% vs 21.1%, p=0.037).<br> <strong>Conclusion:</strong> Atopy is frequently present in patients with CRSwNP and pattern of sensitization can affect the&nbsp;outcome of intervention. With respect to different pattern of sensitization among failed and successful interventions,&nbsp;determining the sensitizations prior to any intervention is suggested. Patient counseling regarding the recurrence&nbsp;of disease can be done in accordance with atopic profile. Chronic rhinosinusitis, Allergy, Asthma, Atopy 1 9 http://ijca.iums.ac.ir/browse.php?a_code=A-10-38-4&slc_lang=fa&sid=1 Ahmad Bahrami 1003194753284600424 1003194753284600424 No Iran University of Medical Sciences, Tehran, Iran. Mohammad Nabavi 1003194753284600425 1003194753284600425 No Tehran University of Medical Sciences, Tehran, Iran Zahra Aryan aryanzahra@yahoo.com 1003194753284600426 1003194753284600426 Yes Tehran University of Medical Science, Tehran, Iran Rezaei Nima 1003194753284600427 1003194753284600427 No Tehran University of Medical Science, Tehran, Iran