What is the treatment for meningitis?

Treatment of Bacterial Meningitis

Bacterial meningitis requires immediate antibiotic therapy, which should be initiated within 1 hour of clinical suspicion, even before diagnostic confirmation. 1

Initial Management

• Start empiric antibiotics immediately upon clinical suspicion of bacterial meningitis, even if lumbar puncture is delayed due to cranial imaging 1
• Blood cultures should be drawn before starting antibiotics if lumbar puncture is delayed 1
• Lumbar puncture should be performed immediately unless contraindicated 1
• Cranial imaging before lumbar puncture is strongly recommended only for patients with:
  • Focal neurologic deficits (excluding cranial nerve palsies) 1
  • New-onset seizures 1
  • Severely altered mental status (Glasgow Coma Scale score <10) 1
  • Severely immunocompromised state 1

Empiric Antibiotic Therapy

Adults <60 years:

• First choice: Ceftriaxone 2g IV every 12 hours OR Cefotaxime 2g IV every 6 hours 1, 2
• Add vancomycin 15-20 mg/kg IV every 12 hours if penicillin-resistant pneumococci are suspected 1, 3

Adults ≥60 years or immunocompromised:

• Ceftriaxone 2g IV every 12 hours OR Cefotaxime 2g IV every 6 hours PLUS Ampicillin/Amoxicillin 2g IV every 4 hours (to cover Listeria monocytogenes) 1, 4
• Add vancomycin if penicillin resistance is suspected 1

Children:

• Initial therapeutic dose: 100 mg/kg of ceftriaxone (not to exceed 4 grams) 2
• Thereafter: 100 mg/kg/day (not to exceed 4 grams daily) 2
• Add vancomycin for suspected pneumococcal meningitis 5, 3

Adjunctive Therapy

• Administer dexamethasone 10 mg IV every 6 hours for adults with suspected or proven bacterial meningitis, especially for pneumococcal meningitis 1
• Start dexamethasone with or shortly before the first antibiotic dose 6

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 15-20 mg/kg IV every 12 hours PLUS rifampicin 600 mg IV/orally every 12 hours 1
• Duration: 10-14 days (10 days if stable, 14 days if slower response or resistant strains) 1

Neisseria meningitidis:

• Continue ceftriaxone/cefotaxime OR use benzylpenicillin 2.4g IV every 4 hours 1
• If not treated with ceftriaxone, add a single dose of 500 mg ciprofloxacin orally 1
• Duration: 5 days if recovered 1

Listeria monocytogenes:

• Amoxicillin 2g IV every 4 hours for 21 days 1
• Alternative: Co-trimoxazole 10-20 mg/kg (of trimethoprim component) in four divided doses 1

Duration of Therapy

• Pneumococcal meningitis: 10 days if recovered by day 10; 14 days if not recovered or resistant strains 1
• Meningococcal meningitis: 5 days if recovered 1
• Listeria meningitis: 21 days 1

Outpatient Antibiotic Therapy Considerations

• May be appropriate after 5 days of inpatient therapy if patient is afebrile, clinically improving, and has reliable IV access 1
• Ceftriaxone 2g twice daily IV (can switch to 4g once daily after first 24 hours) 1
• Patient must have access to medical advice/care from the OPAT team 24 hours a day 1

Common Pitfalls to Avoid

• Delaying antibiotic administration while waiting for diagnostic tests - antibiotics should be started within 1 hour of clinical suspicion 1, 4
• Failing to obtain blood cultures before starting antibiotics 1
• Performing lumbar puncture without considering contraindications that require prior imaging 1
• Using inadequate antibiotic doses or inappropriate combinations for suspected resistant organisms 1
• Omitting vancomycin in areas with high prevalence of penicillin-resistant pneumococci 3