Microscopy

A

A: Pneumocystis jiroveci trophozoites in bronchoalveolar lavage (BAL) material.  Giemsa stain.  The trophozoites are small (size: 1 to 5 µm), and only their nuclei, stained purple, are visible (arrows).  AIDS patient seen in Atlanta, Georgia.

B	C

Pneumocystis jiroveci cysts
B: 3 cysts in bronchoalveolar material, Giemsa stain; the rounded cysts (size 4 to 7 µm) contain 6 to 8 intracystic bodies, whose nuclei are stained by Giemsa; the walls of the cysts are not stained; note the presence of several smaller, isolated trophozoites.
C: Cysts in lung tissue, silver stain; the walls of the cysts are stained black; the intracystic bodies are not visible with this stain; baby who died with pneumonia in California.

D

D: Pneumocystis jiroveci cysts in bronchoalveolar lavage material; silver stain; this greater magnification shows the irregular, saucer shape of the cysts.

E

E: Indirect immunofluorescence using monoclonal antibodies against Pneumocystis jiroveci.  Specimen from a patient with AIDS, seen in Georgia.