Chest computed tomographic findings and clinical features of legionella pneumonia

To describe the chest radiographic and computed tomographic (CT) findings of legionella pneumonia.

Serial chest radiographs and CT scans obtained in 12 patients with serologically proven Legionella pneumophila pneumonia were retrospectively reviewed. Chest CT findings were analyzed with regard to patterns and distributions of pulmonary abnormalities.

Nine of the 12 patients were in an immunocompromised state, that is, steroid therapy (n = 8) and myelodysplastic syndrome (n = 1), and 6 of the 8 steroid users were on high-dose steroid. All patients showed multilobar or multisegmental pulmonary infiltrates on CT scans. The CT findings were categorizable as; predominantly airspace consolidations (n = 6), mixed lesions with lobular consolidation and ground-glass opacity (GGO) (n = 3), and pure GGO lesions (n = 2). Five of the 6 patients on high-dose steroid therapy had lobar consolidations with (n = 4) or without a cavity (n = 1), and 1 patient had a mixed lesion.

The most common CT findings in legionella pneumonia were multilobar or multisegmental consolidation and GGO. Cavitary lobar consolidation occurred commonly in patients on high-dose steroid therapy.