Cytomegalovirus pneumonia: computed tomography findings

Cytomegalovirus (CMV) is a frequent pathogen of the respiratory tract in immunosuppressed patients. The diagnosis of CMV pneumonia frequently requires bronchopulmonary lavage or lung biopsy because the findings on chest radiographs are nonspecific. In only three cases of pure CMV pneumonia has the computed tomography (CT) appearance been described. In this study CT scans and chest radiographs of eight patients with CMV pneumonia were evaluated to determine if a characteristic CT appearance exists. The studies were evaluated for the type, severity and distribution of parenchymal abnormality. The most common CT finding was the presence of mixed alveolar and interstitial disease (seven patients); alveolar disease predominated in five of the seven patients, equal amounts of alveolar and interstitial disease were noted in one and interstitial disease predominated in the remaining patient. Air-space disease alone was present on CT examination of the eighth patient. In no case was there interstitial disease alone. Although mixed alveolar and interstitial disease was the most frequently encountered pattern, the variety of appearances suggests that the CT findings of CMV pneumonia are nonspecific.