Listeria monocytogenes meningitis in previously healthy adults: long-term follow-up.

A few cases of Listeria meningitis in healthy individuals have been recorded in the world literature. The lack of a prolonged follow-up in most of these cases makes it difficult to exclude the existence of an underlying disease. The clinical and CSF data of four previously healthy patients with meningitis due to Listeria monocytogenes are presented. These patients were followed prospectively over 2-6 years; during this time none developed any disease associated with immunosuppression, including HIV infection, and none died. Listeria meningitis in an otherwise healthy person is, therefore, not always a sign of underlying immunosuppressive disease, and does not necessarily have a poor prognosis.