title: Outcome of chronic idiopathic meningitis.
abstract: OBJECTIVE
  To record long-term follow-up data on patients with chronic idiopathic meningitis.
  
  
  METHODS
  We retrospectively reviewed the outcome of 49 patients who were examined at the Mayo Clinic between 1978 and 1990.
  
  
  METHODS
  For all patients, symptoms, signs, laboratory values, results of imaging studies, findings on biopsies, results of any empiric treatment, and results of autopsy, if applicable, were assessed. Some of these findings were stratified on the basis of good versus poor outcome of the patients and were analyzed statistically.
  
  
  RESULTS
  Of the 49 patients who fulfilled the criteria for chronic idiopathic meningitis, 10 had a cause identified after repeated studies, brain biopsy, or autopsy (8 of these had a neoplasm). Of 21 brain biopsies, 5(24%) yielded a diagnosis. Follow-up of the 39 undiagnosed cases showed that 33 (85%) had a good outcome despite an often prolonged illness. Two patients (5%) died of the meningeal process. Of the eight patients treated empirically with antituberculous medications, none responded. Corticosteroid therapy was effective in 52% of the patients thus treated, but it did not influence the outcome.
  
  
  CONCLUSIONS
  In this study, 85% of undiagnosed cases of chronic meningitis were benign. No clinical or laboratory findings predicted those patients who had a fatal outcome. In our study population, the most useful empiric therapy was corticosteroids rather than antituberculous medications.
authors.affiliation: Department of Neurology, Mayo Clinic Rochester, Minnesota 55905.
authors.forename: J E
authors.initials: JE
authors.lastname: Smith
authors.forename: A J
authors.initials: AJ
authors.lastname: Aksamit
mesh_terms: D000328:Adult; D000368:Aged; D002908:Chronic Disease; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008581:Meningitis / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed