Adenovirus
Key Facts
Clinical Issues
Accounts for about 10% of all pneumonias in children and infants
Epidemics have been reported in military personnel
Microscopic Pathology
2 major patterns of lung injury
Necrotizing bronchitis/bronchiolitis with necrosis of walls of airways due to severe acute inflammatory infiltrate
Acute necrotizing alveolitis with hyaline membranes and fibrinous alveolar exudates resembling diffuse alveolar damage (DAD)
“Smudge cell”
Basophilic inclusion that obscures nuclear membrane and fills entire nucleus
Intranuclear eosinophilic inclusions
Surrounded by a halo separating them from nuclear membrane (similar to those seen in HSV)
 Histologic appearance of acute necrotizing alveolitis in a patient with adenovirus pneumonia shows interstitial edema with inflammatory exudates and hyaline membrane formation  similar to DAD. |
 Higher magnification of adenovirus pneumonia shows several intranuclear eosinophilic inclusions. The presence of “smudge cells”  (eosinophilic inclusions filling the nucleus) is distinctive for adenovirus. |
TERMINOLOGY
Definitions
Pulmonary infection caused by adenovirus
ETIOLOGY/PATHOGENESIS
Infectious Agents
> 50 known serotypes
Serotypes 3, 7, and 21 are most common in children
Serotypes 3, 4, and 7 are most common in adults
