[Intractable bacterial infections in the nervous system].

It is not exaggeration to say that infectious meningitis is most often seen among infections of the nervous system caused by various microorganisms, in which viruses are main causative pathogens. Infectious meningitis due to bacteria includes purulent one with acute progress, tuberculous and fungal ones which are representative for subacute meningitis. They can not be easily treated. As brain abscess is similar to them, diagnosis and chemotherapy on these four diseases are briefly summarized here. It is needless to say that the prognosis is influenced by early diagnosis and how fast appropriate chemotherapy is started in all four diseases. Dexamethasone therapy should be tried in purulent meningitis in order to decrease hearing disturbance which is unable to be prevented by chemotherapy.