TABLE 1.

Phases in the pathophysiology of bacterial meningitis

Time (h postinfection)	Pathophysiologic events	Clinical symptoms
0	Bacteria and bacterial products accumulate in CSF	None
4	Release of inflammatory mediators and cytokines	Fever
8-24	Blood-brain barrier disruption; development of cerebral edema; transendothelial migration of leukocytes; more proinflammatory and toxic mediators; followed by impaired cerebral blood flow, elevated intracranial pressure, and vasculitis	Elevated CSF protein; meningism/neck stiffness; elevated CSF leukocytosis; possible systemic complications; followed by altered mental status, focal symptoms, and seizures
24-48	Neuronal injury	Focal symptoms; hearing loss; paralysis; cognitive impairment; death