The Effect of Chronic Infection With Aspergillus fumigatus on Lung Function and Hospitalization in Patients With Cystic Fibrosis

Background: The relevance of Aspergillus fumigatus in patients with cystic fibrosis (CF) not affected by allergic bronchopulmonary aspergillosis is unclear. Our aim was to determine the effect of persistent infection with A fumigatus on pulmonary exacerbations and lung function in children with CF. Methods: This was a retrospective cohort study of patients with CF followed at The Hospital for Sick Children from 1999 to 2006. Persistent A fumigatus infection was defined as the presence of two or more positive sputum or bronchoalveolar cultures for A fumigatus in a given year. The primary outcome measure was the annual number of hospitalizations for pulmonary exacerbations. Results: Two hundred thirty patients with CF were included in the analysis. The FEV1 of patients persistently infected with A fumigatus was 3.61% (P <=.0001) lower during the study period compared with uninfected patients. There was a significant interaction between A fumigatus and Pseudomonas aeruginosa on lung function (P=.0006). Patients not infected with either organism had the highest pulmonary function. Persistent A fumigatus infection (relative risk [RR] = 1.94, P=.0002) and CF-related diabetes (RR=1.64, P=.028) were associated with an increased risk of pulmonary exacerbations requiring hospitalization, whereas there was no increased risk of pulmonary exacerbations among patients with allergic bronchopulmonary aspergillosis (RR=1.02, P=.94). When adjusted for baseline pulmonary function, none of these variables were associated with a significantly increased risk of pulmonary exacerbations, with only chronic A fumigatus infection trending toward significance (RR=1.40, P=.065). Conclusions: Persistent A fumigatus infection is an independent risk factor for hospital admissions in patients with CF. CHEST 2010; 137(1):171-176