IgE-mediated sensitization to mould allergens among patients with allergicrespiratory diseases in a desert environment

Background: The importance of fungal allergens in the development of allerg ic diseases in a desert environment is uncertain. This study evaluated the prevalence of IgE sensitization to moulds among patients with allergic resp iratory diseases in Kuwait - a desert country. Methods: A total of 810 pati ents (male:female ratio 1.4) with a mean age of 32.3 years (range 2-76 year s) with extrinsic asthma or allergic rhinitis were studied. Sera from the p atients were tested by the CAP-RAST method for specific IgE to 6 fungi (Pen icillium, Cladosporium, Aspergillus, Candida, Alternaria and Helminthospori um). For comparison house dust mite and Bermuda grass were also assessed. R esults: The overall positivity to at least one mould was 20.9%. Among 120 m atched control subjects, the value was 5.8%. The value was much higher amon g patients with asthma alone (45.8%) or both asthma and rhinitis (28.3%) th an those with rhinitis alone (11.8%; p < 0.001). Asthmatic children had the highest sensitization rate (66.0% in the 7- to 12-year age group), which d eclined sharply with age. Among asthmatics, Candida and Aspergillus had the highest sensitization rates (23.1 and 21.3%, respectively), followed by He lminthosporium (18.8%), Cladosporium (15.9%), Alternaria (14.6%) and Penici llium (13.9%). The values for mite and Bermuda grass were 41.2 and 54.6%, r espectively. Among asthmatic children, severe asthma was significantly more frequent among mould-positive (51.6%) than mould-negative patients (17.5%; p < 0.0001). Conclusions: Even in this desert environment, sensitization t o moulds is quite common among patients with allergic respiratory diseases, with a striking preponderance among children with asthma. Mould allergy co uld also be an important factor determining asthma severity in this environ ment. Copyright (C) 2000 S. Karger AG, Basel.