Viruses

Herpes simplex (Herpesvirus hominis) and Herpes zoster--Histologic changes are similar for both viruses

Eosinophilic nuclear inclusions (arrows) occur in normal-sized epithelial cells or multinucleated giant cells (asterisk). The inclusion sometimes has a halo between it and the nuclear membrane and sometimes fills the entire space.

A necrotizing pneumonia, shown here, is characteristic of both simplex and zoster viruses. The healed lesions of zoster may calcify.

Immunoperoxidase stain for herpesvirus

The two brown-stained cells in the center of the alveolus are sloughed epithelial cells infected with the virus.

Adenovirus

The inclusions may appear the same as those of H. simplex (left arrow) or as a "smudged," homogeneous nuclear inclusion (right arrow). The structure shown is a bronchial gland.

Paramyxovirus--Rubeola (measles)

Measles pneumonia is characterized by giant multinucleated cells with red nuclear and cytoplasmic inclusions. The cytoplasmic inclusions are very small and dark. This single giant cell (arrow) is part of the alveolar lining. The air space above it is filled with exudate.

Contents