What is the recommended management for meningitis?

Management of Bacterial Meningitis

The recommended first-line treatment for suspected bacterial meningitis is immediate administration of a third-generation cephalosporin (ceftriaxone or cefotaxime) combined with vancomycin, with adjunctive dexamethasone given before or with the first antibiotic dose. 1

Initial Empiric Antimicrobial Therapy

Adults

• Age <60 years:

  • Ceftriaxone 2g IV every 12 hours OR Cefotaxime 2g IV every 6 hours 1
  • PLUS Vancomycin 15-20 mg/kg IV every 12 hours (if penicillin-resistant pneumococci suspected) 1

• Age ≥60 years:

  • Ceftriaxone 2g IV every 12 hours OR Cefotaxime 2g IV every 6 hours
  • PLUS Amoxicillin 2g IV every 4 hours (for Listeria coverage)
  • PLUS Vancomycin if penicillin-resistant pneumococci suspected 1

Children

• Ceftriaxone 100 mg/kg/day IV OR Cefotaxime 300 mg/kg/day IV
• PLUS Vancomycin 60 mg/kg/day if pneumococcal meningitis cannot be ruled out 2

Adjunctive Dexamethasone

• Administer dexamethasone 0.15 mg/kg IV every 6 hours for 2-4 days 1
• First dose should be given 10-20 minutes before or at least concomitant with the first antimicrobial dose 1
• Particularly beneficial for pneumococcal meningitis, with significant reduction in unfavorable outcomes (26% vs 52%) and mortality (14% vs 34%) 1

Duration of Antimicrobial Therapy

• Pneumococcal meningitis:

  • 10 days if recovered by day 10 1
  • 14 days if not recovered by day 10 or if penicillin/cephalosporin resistant 1

• Meningococcal meningitis:

  • 7-10 days of appropriate antibiotic therapy 1

Pathogen-Specific Treatment After Culture Results

Streptococcus pneumoniae

• Penicillin-sensitive (MIC ≤0.06 mg/L):
  • Benzylpenicillin 2.4g IV every 4 hours OR continue ceftriaxone/cefotaxime 1
• Penicillin-resistant but cephalosporin-sensitive:
  • Continue ceftriaxone or cefotaxime 1
• Penicillin and cephalosporin-resistant:
  • Continue ceftriaxone/cefotaxime PLUS vancomycin PLUS rifampicin 600mg IV/oral every 12 hours 1

Neisseria meningitidis

• Continue ceftriaxone/cefotaxime OR benzylpenicillin 2.4g IV every 4 hours 1

Special Considerations

Antimicrobial Resistance

• If patient has traveled to areas with high pneumococcal resistance in the past 6 months, add vancomycin or rifampicin to empirical therapy 1
• When using vancomycin, maintain serum trough concentrations of 15-20 mg/mL 1

Rifampin Use

• Consider adding rifampin when:
  • Treating highly penicillin or cephalosporin-resistant pneumococcal strains 1
  • Using dexamethasone with vancomycin (as dexamethasone reduces vancomycin penetration into CSF) 3
  • The combination of ceftriaxone and rifampin is preferred when dexamethasone is used 3

Supportive Care

• Maintain euvolemia (fluid restriction is NOT recommended) 4
• Maintain mean arterial pressure ≥65 mmHg 4
• Monitor for signs of raised intracranial pressure 4
• Consider ICU admission for patients with GCS <12, persistent seizures, severe sepsis, or hypoxia 4

Common Pitfalls to Avoid

1. Delayed antimicrobial therapy - Bacterial meningitis is a neurological emergency; start antibiotics immediately after blood cultures (or after LP if performed promptly) 1, 4

2. Inadequate coverage for resistant organisms - Always consider the possibility of resistant pneumococci, especially in patients with recent travel history 1

3. Inappropriate use of dexamethasone - Must be given before or with the first antibiotic dose to be effective 1

4. Monotherapy with vancomycin - Vancomycin should never be used as a single agent, even for highly resistant pneumococcal strains 1

5. Fluid restriction - This practice is not recommended and may worsen outcomes 4

By following this algorithmic approach to bacterial meningitis management, focusing on early appropriate antimicrobial therapy and adjunctive dexamethasone, mortality and neurological sequelae can be significantly reduced.