Histopathology of fatal adenovirus infection of the respiratory tract in young children.

Type 7 adenoviruses were isolated from lung tissue obtained at the necropsies on five children aged 8 to 15 months. The clinical and radiological findings were those of bronchiolitis and pneumonia. Four children had an extensive necrotizing bronchitis and bronchiolitis. The surviving bronchial epithelium, and all bronchial epithelium in the fifth case, was proliferating. There was evidence that this proliferation was a virus-induced effect and not reparative. There was virus tropism to alveolar lining cells with a pneumonia showing mononuclear cellular reaction, necrosis, and hyaline membranes. Distinctive necrotizing lesions were found in the bronchial glands of all cases. Two contrasting types of intranuclear inclusions were present in all lesions and their significance and inter-relationships are discussed. These pathological changes are specific for infections by a limited number of adenovirus serotypes.