Analysis of the fungal microbiome in exhaled breath condensate of patients with asthma

Background: The presence of virus and bacteria in the airways of subjects with asthma is common and seems to be associated with a deterioration due to the disease. The microbiologic study of airways in asthma is foreseen by guidelines with induced sputum that is often ineffective and contraindicated in severe asthma. Aim: To analyze the fungal microbiome in the exhaled breath condensate (EBC) of subjects with asthma by evaluating a possible correlation with anthropometric and asthma severity data. Methods: We enrolled 47 consecutive subjects with asthma (28 with atopic asthma and 19 with nonatopic asthma) and 20 controls. Enrolled subjects underwent EBC and sputum collection. Fungal microbiome was assessed by culture on EBC and sputum samples by using Czapek yeast extract agar. Results: A fungal colonization in the EBC of 70% of enrolled subjects with asthma was detected (none detected in the controls). An overlap of fungal microbiome in EBC and sputum was observed (100% of overlap). Fungal colonization was higher in subjects without atopic, obesity, and severe and uncontrolled asthma. Conclusion: When considering the high morbidity and mortality of patients with severe asthma in whom we found an important fungal airways colonization, we support the use of the analysis of exhaled fungal microbiome in these subjects.