g. Alternaria alternate, Penicillium notatum, Aspergillus fumigatus, and Cladosporium), dust mites, cockroaches, and animal dander.11 The considerable

role of aeroallergens as risk factors for allergic disorders was shown in 141 asthmatic patients in our study, which is in accordance with a similar study on 151 asthmatic patients in Saudi Arabia.16 Also, 23.6% of our allergic patients had sensitivity to weeds, which is comparable #Chk2 phosphorylation keyword# to a prevalence rate of 21% reported by a study in Zanjan (Iran).17 Among our asthmatic patients, positive SPT results for trees, weeds, and grasses were closely similar to the results reported by Farhoudi et al.18 and Movahedi and Moin19 in Iran. Fereidouni et al.20 reported that weeds (81%) and grasses (62%) were the most prevalent allergens in 311 patients Inhibitors,research,lifescience,medical with allergic rhinitis. In our asthmatic patients, sensitivity to house dust mites (DP and DF) was 21% and 25%, respectively, which is parallel to the findings by Ceylan et al.15 This resemblance

could be due to the similar geographical characteristics of the two countries. Our results on the sensitivity to mites and trees are highly in agreement with the findings of Safari et al.21 insofar as they Inhibitors,research,lifescience,medical reported prevalence rates of 27.3% and 27.2% among patients sensitive to mites and trees respectively; nevertheless, the findings of our two studies are not consistent vis-à-vis the percentages of patients sensitive to grasses (9%) and cockroaches (27.2%). As was confirmed in our study, pollen levels are usually higher in spring and lower in autumn.22 Accordingly,

there are various manifestations of allergic symptoms in different seasons. Sensitization to the pollens of trees, grasses, and weeds Inhibitors,research,lifescience,medical is higher in spring, and sensitization to house dust mites is elevated in winter for DF and in summer for DP. In contrast, Akarcay et al.23 revealed a significant prevalence of sensitization to pollens and house dust mites, both in spring. Overall, the highest prevalence of asthmatic Inhibitors,research,lifescience,medical and allergic rhinitis patients suffering from all allergens (aero and food allergens) is seen in winter. It is thought that DF is more frequent in dry Methisazone climates, whereas DP is more prevalent in humid climates.23 Cat fur allergen induces rapid respiratory symptoms in individuals sensitized to cats.16 Sensitivity to cat fur allergen was found in 13% of our asthmatic patients. Studies in Iran18 and Spain24 have reported the prevalence rates of 15% and 15.5%, respectively, but studies in Baltimore25and Saudi Arabia16 have reported much higher frequencies. It seems that this difference is due to the genetic factors or lower exposure to cats in the Iranian population. Sensitivity to cat fur was found in 23% of our patients with allergic rhinitis, which is comparable to a study from South Africa.