A 65-year-old diabetic patient presents with bacterial meningitis. CSF: turbid, opening pressure 320 mmH2O, protein 280 mg/dL, glucose 18 mg/dL (blood glucose 95 mg/dL), leucocytes 2400/µL (90% neutrophils). Gram stain shows Gram-negative diplococci. PCR for meningococcal 16S rRNA is pending. Which empirical treatment should be initiated immediately while awaiting culture sensitivity results?
- A IV ampicillin + gentamicin combination empirically
- B IV meropenem 2 g every 8 hours as first-line empirical treatment
- C IV ceftriaxone 2 g every 12 hours + IV dexamethasone 0.15 mg/kg every 6 hours for 4 days ✓
- D IV vancomycin monotherapy for Gram-negative organism coverage
Explanation
Bacterial meningitis management requires immediate empirical antibiotics and adjunctive dexamethasone. Ceftriaxone 2 g IV q12h (or cefotaxime 2 g IV q6h) is the empirical treatment of choice covering the main bacterial pathogens (S. pneumoniae, N. meningitidis, H. influenzae). Dexamethasone 0.15 mg/kg IV q6h for 4 days, started 15–30 minutes before or with the first antibiotic dose, reduces neurological sequelae (especially hearing loss in H. influenzae meningitis and mortality in pneumococcal meningitis in adults). Ampicillin should be added only when Listeria is suspected (age >50, immunocompromised). Vancomycin is added only if penicillin-resistant pneumococcus is suspected.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.