Non-neonatal infection due to Listeria monocytogenes.

In the period from 1969 through 1983, four cases of non-neonatal Listeria monocytogenes meningitis were encountered in Dallas, representing an incidence rate of 0.3%. Three cases occurring in immunocompetent patients are the subject of this report. A review of the literature since 1945 produced 87 cases of Listeria infections in patients who were from 2 months to 20 years of age. Of these, 54% occurred in immunocompetent persons. The case-fatality rate was 15% in the immunocompetent patients, compared with 42% in immunocompromised patients and with 35% in patients with other underlying illnesses. The diagnosis of listeriosis causes concern about the possibility of an underlying occult malignancy or disorder of T cell function, but on the basis of our review these underlying abnormalities are usually clinically apparent at the time of infection. A rational approach to the child with Listeria infection, who is not known to be a compromised host, would be to examine the history and patient carefully to consider documenting normal numbers of T lymphocytes and assessing delayed hypersensitivity by skin testing.