[Infection of the CNS caused by Listeria monocytogenes]

This report examines two cases of infection of the central nervous system by Listeria monocytogenes (L.m.). Both cases show that listeriosis is not only a differential diagnosis of purulent meningitis, but can also be the cause of an isolated brain stem syndrome with normal cerebrospinal fluid cell count. The prognosis depends crucially on the early antibiotic therapy (ampicillin). The first patient was a chronic alcoholic. He died of fulminant septic shock and meningitis with brain stem encephalitis (cell count of cerebrospinal fluid: 10500/microliters). L.m. was isolated from blood cultures and from cerebrospinal fluid. The second patient had no indications of preexisting immunological disorder. Two days after perianal injections for haemorrhoids, symptoms of a progredient brain stem syndrome developed. The cell count of cerebrospinal fluid was only 10/mu, but L.m. was isolated from blood cultures. The patient died of circulatory failure. At autopsy, a brain stem encephalitis and cerebellitis with inflammation of the surrounding leptomeninx was identified.