Steroids in Meningitis
Adjunctive dexamethasone should be administered to adults and children with suspected or proven bacterial meningitis, given 10-20 minutes before or concomitant with the first antibiotic dose, as it significantly reduces mortality, hearing loss, and neurological sequelae, particularly in pneumococcal and H. influenzae type b meningitis. 1
Adult Dosing and Administration
- Dexamethasone 10 mg intravenously every 6 hours for 4 days is recommended for all adults with suspected bacterial meningitis in high-income countries 1
- The first dose must be given 10-20 minutes before or at least concomitant with the first antimicrobial dose for maximum benefit 1
- If antibiotics have already been started, dexamethasone can still be administered up to 4 hours after the first antibiotic dose 1
- In pneumococcal meningitis specifically, dexamethasone reduces unfavorable outcomes from 52% to 26% and mortality from 34% to 14% 1
Pediatric Dosing and Administration
- Dexamethasone 0.15 mg/kg intravenously every 6 hours for 2-4 days for children with suspected bacterial meningitis 1
- The steroid should ideally be administered 10-20 minutes before or concomitant with the first antimicrobial dose 2
- Strongest evidence supports use in H. influenzae type b meningitis, with confirmed reduction in hearing impairment (OR 0.31; 95% CI, 0.14-0.69) 1
- For pneumococcal meningitis in children, evidence suggests benefit for severe hearing loss when given early (OR 0.09; 95% CI, 0.0-0.71) 1
Mechanism of Benefit
The rationale for dexamethasone is based on its ability to attenuate the subarachnoid space inflammatory response, which is a major contributor to morbidity and mortality in bacterial meningitis 1. Specifically, it:
- Decreases cerebral edema and increased intracranial pressure 1
- Reduces altered cerebral blood flow and cerebral vasculitis 1
- Prevents neuronal injury mediated by pro-inflammatory cytokines 1
When to Discontinue Dexamethasone
- Stop dexamethasone if the patient is discovered not to have bacterial meningitis 1
- Discontinue if the causative organism is neither H. influenzae nor S. pneumoniae, although some experts advise continuing regardless of the causative organism 1
- For N. meningitidis meningitis, the benefit is less clear due to lower event rates and smaller numbers in studies 1
Special Populations and Caveats
Neonates
- Dexamethasone is not currently recommended for neonatal bacterial meningitis 1
Low-Income Countries
- No beneficial effects have been identified in studies performed in low-income countries 1
Tuberculous Meningitis
- For TB meningitis, use dexamethasone 0.4 mg/kg/day (maximum 12 mg/day) intravenously for 3 weeks, then taper over the following 3 weeks 3
- Alternatively, prednisolone 60 mg/day tapered over 6-8 weeks can be used 3
- Corticosteroids should be initiated before or concurrently with the first dose of anti-tuberculosis medication 3
Evidence Quality Considerations
While a 2016 meta-analysis suggested that dexamethasone might not significantly reduce mortality or severe neurological sequelae overall 4, the guideline recommendations from the Infectious Diseases Society of America and American Academy of Pediatrics take precedence 1, as they incorporate broader clinical context and pathogen-specific benefits. The meta-analysis did confirm reduction in hearing loss (OR 0.76; 95% CI 0.59-0.98) 4, which aligns with guideline recommendations emphasizing audiological benefits.
Common Pitfalls to Avoid
- Do not delay dexamethasone administration - timing is critical, and benefit is maximized when given before or with antibiotics 1
- Do not withhold dexamethasone due to concerns about antibiotic penetration - while dexamethasone may decrease CSF antibiotic concentrations, the overall clinical benefit outweighs this theoretical concern when appropriate antibiotics are used 5
- Do not continue dexamethasone if bacterial meningitis is ruled out - unnecessary steroid exposure should be avoided 1