The role of corticosteroid therapy on bacterial meningitis in adults

Most clinical trials on the efficacy of corticosteroid as adjuvant therapy of community-acquired bacterial meningitis have been carried out in pediatric populations and thus in Haemophilus influenzae meningitis. The higher mortality rate and neurological sequela observed in adults raised questions as to the efficacy of this treatment. As demonstrated in animal experimental models, some components of the Streptococcus pneumoniae cell wall have the same effects as the LPS of H. influenzae on the activation of the local inflammatory chain. Early administration of dexamethasone reduces the consequences of the meningeal inoculation particularly for cerebral edema. Data on patients sub-groups with pneumococcal meningitis, in a Cairo hospital, may suggest beneficial effect of early dexamethasone treatment on hearing sequela of pediatric patients and on the mortality rate of adults patients. We carried out a randomized double-blind clinical trial on the efficacy of dexamethasone (10 mg q.i.d. during the first three days) in bacterial meningitis of adults treated with parental amoxicillin. Among the 60 included patients, 83% were hospitalized in an ICU and 43% required endotracheal intubation. S. pneumoniae was isolated in 31 patients, with a reduced susceptibility to penicillin in five cases, and Neisseria meningitidis in 18 patients. The overall cure rate-without any neurological sequela at day 30- was 51% in the placebo group and 74% in the dexamethasone group (NS). No major adverse effect was observed in the dexamethasone group and gastro-duodenal bleeding was observed in two patients of the placebo group. Indisputable group and gastro-duodenal bleeding was observed in two patients of the placebo group. Indisputable arguments on the efficacy of a complementary corticosteroid therapy in adult bacterial meningitis are still lacking. This is due mostly to the absence of: well designed trials, or statistically relevant trials. The increasing resistance of S. pneumoniae to betalactam antibiotics will probably delay answering this important question decrease the intra-meningeal diffusion of most available antibiotics and particularly impair the diffusion of glycopeptides.