Trichophyton sensitivity in allergic and nonallergic asthma

Background: Although the role of inhaled fungi in inducing asthma has been repeatedly confirmed, there are few reports about the association of asthma with dermatophyte sensitivity and the causal role of Trichophyton allergy in asthma. The objective was to investigate the presence of Trichophytan se nsitivity among patients with allergic and nonallergic asthma in combinatio n with tinea, and to compare the situation with several control groups in o rder to evaluate the factors determining Trichophyton sensitivity. Methods: A total of 86 subjects (55 female, 31 male) with a mean age of 38. 6 +/- 11.1 years were included in the study. The patients were divided into five groups: 1) nonallergic asthma plus tinea (n = 19) 2) allergic asthma plus tinea (n = 15) 3) asthma without tinea (n = 22) 4) tinea without asthma (n = 17) 5) healthy controls (n = 13). Skin tests with standardized extracts of T rubrum and specific IgE measurem ents were performed in all subjects. All patients were also subjected to mi croscopic evaluation and fungal culture for dermatophyte infection. Results: The skill test positivity rate to Trichophyton extract of groups 1 (63.1%), 2 (46.7%), and 4 (47.1%) was higher than chat in groups 3 (4.4%) and 5 (7.7%) (P <0.05). Although not significant, the rates of sensitivity to T. rubrum (63.1%) and of severe asthma (31.6%) were higher in the group with nonallergic asthma with fines (group 1) than in other groups. Among 51 patients in whom direct microscopic evaluation revealed dermatophyte infec tion, 60.8% had positive fungal cultures for T. rubrum (58.1%), T. mentagro phytes (35.5%), and Candida (6.4%). Conclusions: According to our data, the presence of fungal infection seems to be an important determinant in hypersensitivity to Trichophyton whether or not the subject is asthmatic and/or allergic. Since a greater proportion oi patients with nonallergic asthma - in whom the rate of severe asthma wa s also higher - showed positive skin tests to Trichophyton extracts in this study, We believe that patients with severe, intrinsic asthma should be ex amined for signs of fungal infection and tested to determine immediate hype rsensitivity to dermatophyte antigens.