Chest CT findings and clinical features in mild Legionella pneumonia.

OBJECTIVE: To evaluate mild Legionella pneumonia (LP) by chest CT, and clinical features.

PATIENTS: In June 2000, an outbreak of LP occurred in Japan. Eight patients with mild LP (seven men, one woman; mean age 55.9 years) had fevers of more than 38 degrees C, but respiratory symptoms were observed only in four. Chest CT was performed before starting an appropriate treatment.

MEASUREMENT: CT images were assessed by the distribution of ground-glass opacity (GGO), consolidation, and the existence of pleural effusion.

RESULTS: Chest CT findings: multiple segments were affected in all of the patients, (pleural effusion in three, peripheral lung consolidation in seven, and GGO in seven). GGO was located around the consolidation in six patients.

CONCLUSION: Mild LP may present as fever without respiratory symptoms. Chest CT findings of mild LP are bilateral, multiple affected segments and peripheral lung consolidation with GGO.