Correlation of IgE antibody titer to Aspergillus fumigatus with decreased lung function in cystic fibrosis.

Obstructive pulmonary disease is a typical feature of cystic fibrosis (CF) and is often associated with bronchial hyperreactivity. Positive skin-test reactions to Aspergillus fumigatus antigens are frequently seen even in nonatopic patients with CF. Full-fledged allergic bronchopulmonary aspergillosis (ABPA) has been estimated to occur in 10% of patients with CF. The relationship between lung function and presence of IgE antibodies to Aspergillus antigens in patients without ABPA is not clear. In 148 outpatients with CF (aged 6-34 years) specific immunoglobulin E (IgE) to Aspergillus fumigatus antigens, basic lung-function parameters, and bronchial response to salbutamol were measured. Multiple regression was performed for age, weight as percentile for actual height (indicating general condition), and Aspergillus RAST. Aspergillus IgE was present in 46% of patients; 19% had RAST class 3 or 4. Independent negative correlations of Aspergillus RAST with FEV1, FEF50%, FEF25%, RV, Chrispin Norman score, and sRaw (P less than 0.05) were found. Bronchodilator sensitivity did not correlate significantly with age and weight percentile. However, Aspergillus RAST did correlate significantly with bronchodilator response measured by sRaw (P less than 0.05). High titers of Aspergillus RAST might serve as a selective criterion for patients to be included in future studies evaluating broncholytic or antiphlogistic therapies.