[Confusion and unexplained fever in an elderly man: a case report].

We report the story of a 81 year old man referred for confusion and unexplained hyperthermia. He had no meningeal sign. Routine emergency examinations (CT scanner and lumbar punction) were not contributory, but, later, PCR for herpes virus was highly positive and cerebral CT scan showed the temporal lobe necrosis typical of an herpes virus meningoencephalitis. This severe neurologic emergency is then shortly discussed.