Chronic meningitis in patients with dental infections.

4 patients with a history of initial fever 2--4 weeks passing on to fever peaks every 3rd to 6th day with afebrile intervals repeating for months are presented. Three of them had dental infectious foci mainly in maxillar teeth and 1 patient was treated by a dentist 1 month before onset. None showed meningism or clinical signs of encephalitis. Extensive investigations resulted only in findings from the central nervous system. The EEG was slightly pathological in all cases and papilloedema was found in 2 cases. In the cerebrospinal fluid (CSF) a pleocytosis extending over months, transient presence of plasma cells and increased proteins in the gamma region on agar electrophoresis was found. In 1 case antigen from Streptococcus milleri, a commensal of the mouth flora at times isolated from infectious dental foci, was detected in CSF by counterimmunoelectrophoresis 6 weeks after onset of the disease. Treatment with penicillin had no effect on the fever. Three patients received antiphlogistic drugs with benefit and their dental foci were treated by a dentist.