What is the recommended treatment for meningitis?

Treatment of Bacterial Meningitis

The recommended empiric treatment for suspected bacterial meningitis is a third-generation cephalosporin (ceftriaxone 2g IV every 12 hours or cefotaxime 2g IV every 6 hours), with additional agents based on age, risk factors, and local resistance patterns. 1

Empiric Treatment Algorithm

For adults <60 years:

• First choice: Ceftriaxone 2g IV every 12 hours OR Cefotaxime 2g IV every 6 hours 1
• Alternative (if severe beta-lactam allergy): Chloramphenicol 25mg/kg IV every 6 hours 1

For adults ≥60 years or immunocompromised:

• First choice: Ceftriaxone 2g IV every 12 hours OR Cefotaxime 2g IV every 6 hours
• PLUS: Amoxicillin 2g IV every 4 hours (for Listeria coverage) 1

Additional considerations:

• If risk of penicillin-resistant pneumococci (recent travel to areas with high resistance rates): Add Vancomycin 15-20mg/kg IV every 12 hours (target trough 15-20 μg/mL) OR Rifampicin 600mg IV/oral every 12 hours 1, 2
• Adjunctive dexamethasone: 10mg IV every 6 hours for 4 days, ideally started before or with the first antibiotic dose 1

Pathogen-Specific Treatment

Streptococcus pneumoniae:

• If penicillin-sensitive (MIC ≤0.06 mg/L): Continue ceftriaxone/cefotaxime OR switch to benzylpenicillin 2.4g IV every 4 hours 1
• If penicillin-resistant but cephalosporin-sensitive: Continue ceftriaxone/cefotaxime 1
• If both penicillin and cephalosporin-resistant: Continue ceftriaxone/cefotaxime PLUS vancomycin PLUS rifampicin 1
• Duration: 10-14 days (stop at day 10 if recovered; continue to day 14 if not recovered or resistant organism) 1

Neisseria meningitidis:

• Treatment: Continue ceftriaxone/cefotaxime OR switch to benzylpenicillin 2.4g IV every 4 hours 1, 3
• If not using ceftriaxone: Add single dose of ciprofloxacin 500mg orally (for eradication of carriage) 1, 3
• Duration: 5-7 days (can stop at day 5 if clinically recovered) 1, 3

Haemophilus influenzae:

• Treatment: Continue ceftriaxone/cefotaxime 1
• Duration: 10 days 1

Listeria monocytogenes:

• Treatment: Amoxicillin/ampicillin 2g IV every 4 hours 1
• Duration: 21 days 1

Important Clinical Considerations

1. Timing is critical: Antibiotics should be administered immediately after blood cultures are obtained, without waiting for CSF results if there will be a delay in performing lumbar puncture 1

2. Monitoring response: If no clinical improvement within 48 hours, consider repeat lumbar puncture, evaluation for complications, or assessment for antibiotic resistance 1

3. Dexamethasone considerations: Most beneficial in pneumococcal meningitis; consider discontinuing if pathogens other than S. pneumoniae or H. influenzae are identified, particularly for Listeria (associated with increased mortality) 1

4. Dosing optimization: While the standard ceftriaxone dosing is 2g every 12 hours, some institutions may use 2g once daily for highly susceptible organisms after identification and susceptibility testing 4

5. Outpatient therapy: Consider for patients who are clinically stable after initial inpatient treatment 1

Common Pitfalls to Avoid

• Delaying antibiotics while waiting for diagnostic procedures - this increases mortality risk
• Failing to cover Listeria in patients ≥60 years or immunocompromised
• Neglecting to add vancomycin when penicillin-resistant pneumococci are suspected
• Overlooking the need for ciprofloxacin when treating with benzylpenicillin instead of ceftriaxone for meningococcal disease
• Stopping antibiotics too early before adequate treatment duration is completed
• Not adjusting therapy based on culture results and susceptibility patterns

By following this evidence-based approach to bacterial meningitis treatment, clinicians can optimize outcomes and reduce mortality and long-term neurological sequelae.