Abstract
Experimental studies of bacterial meningitis have shown that components of bacterial cell walls stimulate the local production of inflammatory cytokines in the cerebrospinal fluid, leading to inflammation and alterations in the cerebral microvasculature. Animal studies and clinical trials have demonstrated that adjunctive corticosteroid therapy reduces the production of cytokines in the CSF. This results in decreased severity of the inflammatory process and fewer neurologic sequelae. These data support the use of adjunctive dexamethasone in infants and children with S. pneumoniae and H. influenzae type B (HiB) meningitis. There is not sufficient evidence supporting the use of adjunctive corticosteroid therapy in children with meningitis caused by N. meningitidis. Also, the routine use of dexamethasone in adult meningitis cannot presently be recommended. When using dexamethasone timing is crucial. Administration before or with antibiotics is optimal for attenuating the subarachnoid space inflammatory response. Patients receiving the therapy need careful monitoring for the possibility of gastrointestinal bleeding. Future studies of the pathogenesis and pathophysiology of bacterial meningitis may lead to the development of other adjunctive treatment strategies, improving the outcome of this serious disease.