Table 3.
Cytopathologic effects of CMV, HSV, and adenoviral pneumonias
| Cytopathologic Findings | CMVa | HSVb | Adenovirus |
|---|---|---|---|
| Cytopathic effects | + | + | + |
| Intranuclear inclusions | Early | Late | |
| Intracytoplasmic inclusions | Late | – | Early (multiple, small) |
| Late (large dense) | |||
| Cytomegalia (enlarged infected cell size) | +++ | ++ | + |
| Intranuclear Inclusions | |||
| Ground glass appearance | – | + | – |
| Prominent perinuclear halo | + | – | + (Late) |
| Kidney bean–shaped nucleus (nuclear molding) | –e, f | +e | – |
| Multinucleated giant cells (syncytia) | – | + | – |
| Eosinophilic intranuclear inclusions | –c | + | +d (Early) |
| Nucleolus (basophilic) accessory body | + | – | – |
| Smudged nucleus | – | – | + |
| Intracytoplasmic Inclusions | |||
| Dense (basophilic) granular inclusions | +f | – | – |
Adapted from Cunha BA. Pneumonia essentials. 3rd edition. Sudbury (MA): Jones and Bartlett; 2010; with permission.
a
CAP.
b
CAP or Late-onset VAP.
c
May be eosinophilic early.
d
Small.
e
Gomori methenamine silver stain (GMS).
f
GMS positive and periodic acid-Schiff stain positive.