Cryptococcus pneumonitis

(A) Photomicrograph of a biopsy specimen shows interstitial pneumonitis. Alveolar airspaces are filled with numerous macrophages containing small, cyst-like spaces (arrows).
(B) Magnified view shows the spaces to contain clusters of oval to round yeasts that have mucicarmine positive capsules (arrows). The patient was a 61-year-old man.