[Listeriosis in the nonpregnant adult during an epidemic outbreak on Grand Canary].

Twenty-two cases of community-acquired epidemic listeriosis were recorded from December 31st, 1991, to May 15th, 1993, at the Nuestra Señora del Pino Hospital, Las Palmas. The incidence during this outbreak was 31 times higher than the corresponding incidence in the last few years. Twelve cases occurred in pregnant women and/or neonates and ten in non-pregnant adult individuals. Our aim was to study the clinical, biological, radiological, and evolutive issues in non-pregnant adult patients. Six patients had some immunosuppressive condition: cancer, chemotherapy, AIDS, diabetes, and alcoholism. Eight patients had documented involvement of central nervous system: 6 cases of meningitis and 3 of cerebritis (one case had both meningitis and cerebritis); in the remaining two patients associated with seizures and acute confusional states, respectively. A neurological involvement was not documented because of the fulminant clinical course. CSF examination revealed mononuclear predominance in half of meningitis cases and was normal in two of the three cerebritis cases. The mean time from admission to diagnosis was 3.5 days. All patients but the two who died in the first hours of the disease received ampicillin and an aminoglycoside. The response to therapy was excellent with exception of one patient with meningitis who died in the fourth day of therapy. The clustering of listeriosis cases should alert physicians about the possibility of an epidemic outbreak. Listeria infection in non-pregnant adult individuals in this outbreak showed a high rate of neurological involvement, with focal cerebritis and pleocytosis with a mononuclear predominance in meningitis.