From the Guidelines
The recommended empiric antibiotics for bacterial meningitis in adults include a combination of vancomycin plus a third-generation cephalosporin (either ceftriaxone or cefotaxime), as stated in the most recent guideline from 2017 1.
Empiric Antibiotic Treatment
Typical dosing is vancomycin 10-20 mg/kg IV every 8-12 hours plus ceftriaxone 2g IV every 12 hours or cefotaxime 2g IV every 4-6 hours.
- For patients over 50 years or those with immunocompromise, ampicillin 2g IV every 4 hours should be added to cover Listeria monocytogenes.
- In patients with severe penicillin allergy, meropenem 2g IV every 8 hours can replace the cephalosporin.
Adjunctive Treatment
Dexamethasone 0.15 mg/kg IV every 6 hours for 2-4 days should be administered before or with the first antibiotic dose to reduce inflammation and improve outcomes, particularly in pneumococcal meningitis, as supported by studies 1.
Duration of Treatment
The duration of antibiotic therapy depends upon which pathogen is identified, with recommendations ranging from 5 days for meningococcal disease to 10 days for pneumococcal disease, as suggested by guidelines from 2016 1.
Pathogen Coverage
This broad empiric coverage is necessary because bacterial meningitis is life-threatening and requires immediate treatment before culture results are available.
- The combination targets the most common pathogens: Streptococcus pneumoniae (potentially resistant), Neisseria meningitidis, and Haemophilus influenzae, while vancomycin addresses potential drug-resistant pneumococci.
- Once the causative organism is identified and susceptibilities are known, therapy should be narrowed accordingly, as recommended by the ESCMID guideline 1.
From the FDA Drug Label
When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy MENINGITIS Caused by Haemophilus influenzae, Neisseria meningitidis or Streptococcus pneumoniae Central nervous system infections, e.g., meningitis and ventriculitis, caused by Neisseria meningitidis, Haemophilus influenzae, Streptococcus pneumoniae, Klebsiella pneumoniae* and Escherichia coli*
The recommended empiric antibiotics for bacterial meningitis are:
- Ceftriaxone 2
- Cefotaxime 3 These antibiotics are effective against common causes of bacterial meningitis, including Haemophilus influenzae, Neisseria meningitidis, and Streptococcus pneumoniae.
From the Research
Empiric Antibiotics for Bacterial Meningitis
The choice of empiric antibiotics for bacterial meningitis depends on various factors, including the suspected causative organism and its antimicrobial susceptibility.
- For pneumococcal meningitis, the combination of vancomycin and ceftriaxone is recommended as initial empiric therapy until susceptibility results are available 4.
- Ceftriaxone is effective against a wide range of bacteria, including Haemophilus influenzae, Neisseria meningitidis, and Streptococcus pneumoniae 5, 6.
- The dosing regimen of ceftriaxone may vary, with some studies suggesting that a total daily dose of 2 g may be associated with similar outcomes to a 4 g total daily dose, provided that the causative organism is highly susceptible to ceftriaxone 7.
- For infants and children, combination treatment including cefotaxim or ceftriaxone and vancomycin is recommended as first-line therapy if pneumococcal meningitis cannot be ruled out 8.
- The choice of antibiotic therapy should be adapted according to the clinical and bacteriological response, and second-line therapy may be necessary in cases of resistant organisms or poor clinical response 8.