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Meningitis in elderly patients

Samuel Delerme1, Samuel Castro, Alain Viallon

  • 1Departments of Emergency Medicine and Surgery, Centre Hospitalo-Universitaire Pitie-Salpetriere, Assistance-Publique Hopitaux de Paris, UPMC-Paris 6, Paris, France.

European Journal of Emergency Medicine : Official Journal of the European Society for Emergency Medicine
|June 16, 2009
PubMed

Insights

Bacterial meningitis is more common in elderly patients presenting with atypical symptoms and encephalitis signs. Herpes simplex virus 1 was a frequent cause of nonbacterial meningitis in this age group.

Area of Science:

  • Neurology
  • Infectious Diseases
  • Geriatrics

Background:

  • Meningitis is rare in elderly emergency department (ED) patients.
  • Understanding the differences between bacterial meningitis (BM) and nonbacterial meningitis (NBM) in older adults is crucial.

Purpose of the Study:

  • To compare the characteristics of bacterial meningitis (BM) and nonbacterial meningitis (NBM) in elderly patients.
  • To identify differences in presentation and causative agents between younger and older meningitis patients.

Main Methods:

  • A prospective multicenter study in EDs of three teaching hospitals.
  • Inclusion of 159 adult patients with confirmed meningitis (CSF leukocyte count > 5 mm).
  • Analysis of 18 patients aged 60 years or older.

Main Results:

  • Older patients (≥60 years) had a higher prevalence of BM (50%) compared to younger patients (11%).
  • Elderly patients presented with less typical meningitis symptoms and more frequent signs of encephalitis.
  • Cerebrospinal fluid (CSF) parameters differed between NBM and BM in older adults.
  • Herpes simplex virus 1 was a common cause of NBM in older adults.

Conclusions:

  • Bacterial meningitis is more prevalent in elderly patients.
  • Atypical presentations and encephalitis signs are more common in older adults with meningitis.
  • Herpes simplex virus 1 is a significant cause of NBM in the elderly.

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