A fungus ball composed of blue-staining hyphal elements of Aspergillus is seen here in a bronchus. Fungus balls may also form when fungi colonize cavitary lesions of tuberculosis.

• 支气管处可见由蓝色的菌丝构成的真菌球。当真菌在因结核损害形成的腔洞内植入时，就可能形成真菌球。