High-resolution computed tomography and pathologic findings in pulmonary aspergillosis: a pictorial essay

Aspergillus can cause a wide spectrum of pulmonary complications. It may colonize pre-existing cavities to form mycetomas. In asthmatic patients it may lead to a hypersensitivity reaction involving eosinophilic infiltration of the bronchial wall and mucoid impaction (a condition called allergic bronchopulmonary aspergillosis) or granulomatous inflammation (bronchocentric granulomatosis). In the immunocompromised host, Aspergillus may invade blood vessels, causing hemorrhagic infarction (angioinvasive aspergillosis), or it may cause tracheobronchitis, bronchiolitis or pneumonia (airway invasive aspergillosis), as well as abscess formation with or without adjacent tissue invasion. Each of the manifestations of Aspergillus infection has a distinct histologic and high-resolution computed tomography (CT) appearance. This pictorial essay reviews the characteristic high-resolution CT and corresponding pathologic findings of pulmonary complications due to Aspergillus fumigatus.