Objective: To describe 2 patients presenting with severe neurological deficits and extensive lesions on brain magnetic resonance imaging after having experienced Legionella pneumonia. Design: Case... Show moreObjective: To describe 2 patients presenting with severe neurological deficits and extensive lesions on brain magnetic resonance imaging after having experienced Legionella pneumonia. Design: Case reports. Setting: University hospital. Patients: Two patients who developed severe neurological symptoms, including encephalopathic signs, following Legionella infection, with widespread lesions on magnetic resonance imaging compatible with demyelination. Results: After extensive ancillary investigations, a diagnosis of acute disseminating encephalomyelitis was considered most likely. Steroid therapy was initiated in 1 of the patients, followed by plasmapheresis. In both patients, clinical and radiological signs gradually recovered, with only slight residual deficits. Conclusion: In patients presenting with neurological symptoms after an episode of pneumonia, Legionella infection and a subsequent immune-mediated process such as acute disseminating encephalomyelitis should be considered. Show less