LAUSR

Introduction Small fungal spores of the mold Aspergillus fumigatus (AF), which is abundant worldwide, can easily reach the lower airways and alveoli through inhalation (1, 2). In patients with asthma, the prevalence of Aspergillus sensitization is reported to be about 2% and it is more often associated with severe type of asthma (3). The major types of respiratory disease caused by these fungi are Aspergillus-induced asthma (AIA), severe asthma with fungal sensitization (SAFS), and allergic bronchopulmonary aspergillosis (ABPA) in patients with asthma (4, 5). Patients with asthma who have an immediate positive reaction to the Aspergillus allergen without evidence of inflammation or tissue damage are considered to have AIA (2). The term SAFS was introduced in 2006 for patients with asthma who had an immediate positive skin reaction to Aspergillus antigens or elevated serum IgE levels to AF accompanied by frequent exacerbations of respiratory symptoms (4, 5). ABPA is a complex pulmonary disease characterized by deterioration of lung function, elevated total serum IgE, elevated serum IgE and/or serum IgG to AF, recurrent transient chest X-ray infiltrate s, and peripheral eosinophilia; nevertheless, the key sign is skin test reactivity to Aspergillus (6, 7). In patients with asthma, ABPA is sometimes diagnosed without evidence of typical proximal bronchiectasis; such cases are considered seropositive ABPA (ABPAS) (6). Shiraz is a city in Southwestern Iran which is influenced by dust storms originating from Arabic countries. The present study was designed to determine the frequency of sensitization to Aspergillus and the prevalence of ABPA and SAFS in individuals with severe asthma in Southwestern Iran. This cross sectional study involved adult patients with severe asthma who were referred to the Allergy Clinic Center at Ali-Asghar hospital, affiliated to Shiraz University of