Cerebellar involvement in legionellosis.

The involvement of the cerebellum in Legionnaires' disease has been noted in occasional case reports, but there have been no reviews on this subject to date. We report a previously healthy patient who contracted Legionella pneumonia and developed profound cerebellar dysfunction during his illness. He was treated with antibiotics with improvement of his pneumonia, but his cerebellar symptoms persisted. We review 29 case reports of cerebellar dysfunction in Legionnaires' disease and summarize the clinical course, cultures, cerebrospinal fluid analyses, and neuroimaging. Finally, possible methods of pathogenicity are discussed including data regarding direct bacterial invasion, toxin production, and immune-mediated mechanisms.