Meningitis / Cerebritis / Intracranial Abscess

  • Etiology: organisms responsible
    — Neonates – Group B streptococcus (most common), Escherichia coli, Enterobacter, Citrobacter
    — Infants – Streptococcus pneumoniae (most common), Neiseria meningitidis, Haemophilus influenzae
    — Children – Neiseria meningitidis
  • MRI:
    — Meningitis – lack of sulcal suppression / CSF non suppressed on FLAIR and thickened enhancing meninges
    — Abscess – T2 hypointensity – think / smooth enhancing ring due to hemorrhage + paramagnetic free radicals in macrophages / enhancing ring / restricted diffusion = pus
  • Complications: communicating hydrocephalus due to obstruction at arachnoid villi -> transependymal flow
  • Clinical: subdural effusion during treatment of meningitis does not necessarily mean treatment failure

Cases of Meningitis / Cerebritis / Abscess