[A case of Legionnaires' disease with abnormal neurological findings showing the corpus callosum abnormality on brain MRI].

A 47-year-old man was admitted to our hospital because of dysarthric speech and high fever. His brain magnetic resonance imaging (MRI) showed high intensity in the splenium of the corpus callosum (SCC) on diffusion-weighted and FLAIR imaging. His chest CT showed ground-glass attenuation in bilateral lung upper lobes, and consolidation in the right lower lobe. Because of his neurological findings and radiographic imaging, we started antibiotic therapy using quinolone, which is effective for Legionellosis. Later, Legionella species were identified by sputum culture. Pneumonia was relieved after antibiotic therapy and in parallel with clinical improvement, and the MRI findings also resolved. We report a patient who showed abnormal neurological findings and abnormality on brain MRI, both of which were reversible, in the setting of acute Legionnaires' disease.