Summary A previously healthy woman of 37 years was referred to hospital with a four-day history of fever, meningeal and brain-stem symptoms. Her condition deteriorated and she died four days after admission. At autopsy, microaerophilic Streptococcus and Bacteroids spp. were cultured from pus around the leptomeninges. Neuropathologically, purulent meningitis was evident. Clinically, the picture corresponded to brain-stem meningoencephalitis. No infective focus outside the central nervous system was found. Diagnostic and therapeutic problems and the role of the intra-uterine device are discussed.