Multiple pulmonary Aspergillus fumigatus cysts and cavities that disappeared with anti‐fungal agents

A 26‐year‐old man with a 10‐year history of asthma was admitted to our hospital with a six‐week history of dry cough and slight fever. We observed the left pneumothorax with multiple cysts and cavities and performed partial cystectomy of the left upper lung. Y‐shaped mycelia were detected in the resected tissue, and Aspergillus fumigatus was cultured. Pulmonary aspergillosis was diagnosed from the histopathological and bacteriological findings, and the patient demonstrated positive immunological reactions to A. fumigatus. After administration of an intravenous antifungal agent for one month and an oral antifungal agent for another three months, all cysts and cavities disappeared. Aspergillus infection usually results from saprophytic growth within pre‐existing cavities. In this case, multiple cysts and cavities may have been caused by Aspergillus, possibly through a check‐valve mechanism.