Skip to Main Content


Source: Elshaboury RH, Ahiskali AS, Holt JS, Rotschafer JC. Central nervous system infections. In: DiPiro JT, Talbert RL, Yee GC, Matzke GR, Wells BG, Posey LM, eds. Pharmacotherapy: A Pathophysiologic Approach. 10th ed. New York, NY: McGraw-Hill; 2017. Accessed May 1, 2017.


  • Spinal meningitis.

  • Central nervous system (CNS) infection.


  • Infections within the CNS resulting from.

    • Hematogenous spread from primary infection site.

    • Seeding from parameningeal focus.

    • Reactivation from latent site.

    • Trauma.

    • Congenital defects in CNS


  • Most common causes: Streptococcus pneumoniae, group B Streptococcus, Neisseria meningitidis, Haemophilus influenza, and Listeria monocytogenes

  • Availability of pneumococcal and H. influenzae vaccines has resulted in decreased incidence.


  • Critical first step: nasopharyngeal colonization of host by bacterial pathogen.

    • Bacteria first attach themselves to nasopharyngeal epithelial cells, then are phagocytized into host’s bloodstream.

    • CNS bacterial pathogens have extensive polysaccharide capsule resistant to neutrophil phagocytosis and complement opsonization.

  • Neurologic sequelae of meningitis occur due to activation of host inflammatory pathways.

    • Bacterial cell wall components released, causing capillary endothelial cells and CNS macrophages to release cytokines.

    • Blood-brain barrier altered by proteolytic products and toxic oxygen radicals.

    • Coagulation cascade activated by platelet-activating factor.

    • Vasodilation stimulated by arachidonic acid metabolites.

  • Lead to.

    • Cerebral edema.

    • Elevated intracranial pressure.

    • Cerebrospinal fluid (CSF) pleocytosis.

    • Decreased cerebral blood flow.

    • Cerebral ischemia.

    • Death.


  • Between 2003 and 2007, approximately 4100 cases of acute community-acquired bacterial meningitis, excluding epidemics, occurred annually in the United States, resulting in about 500 deaths.

  • Neurologic sequelae frequently seen include.

    • Seizures.

    • Sensorineural hearing loss.

    • Hydrocephalus.

  • Risk for development of sequelae depends on infecting organism; highest risk associated with pneumococcal meningitis.


  • Vaccines available for certain types of meningitis described in Treatment: Special Considerations section.


  • Passive and active exposure to cigarette smoke.

  • Presence of cochlear implant that includes positioner.


  • Changes in CSF can be used as diagnostic markers of infection (Table 1).

  • Varies with age.

    • Clinical picture more atypical and less pronounced in younger patients.

TABLE 1.aMean Values of Components of Normal and Abnormal Cerebrospinal Fluid

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.