Neuropathologic evaluation of 40 confirmed cases of Legionella pneumonia.

Autopsy examination of the brain was performed in 40 cases of Legionella pneumonia. Thirty-nine of 40 patients had underlying chronic or acute medical problems. Sixteen patients (40%) had neurologic signs or symptoms that were not explained by preexisting disease. CSF was normal in six of seven patients examined; CSF protein content was 66 mg/100 ml in one patient. Neuropathologic examination in all 40 patients demonstrated no lesions attributable to disseminated Legionella pneumophila. Mechanisms other than direct cerebral invasion by the causative organism must be sought to explain the neurologic manifestations of Legionella pneumonia.