A 6-month-old infant with sickle cell disease (HbSS) presents with 2 days of fever (39.5°C), irritability, and bulging anterior fontanelle. CSF shows 1200 WBCs (90% neutrophils), protein 180 mg/dL, glucose 20 mg/dL (blood glucose 90 mg/dL), and a CSF Gram stain showing Gram-negative diplococci. The MOST appropriate antibiotic choice is:
- A Ampicillin + gentamicin
- B Ceftriaxone 100 mg/kg/day IV ✓
- C Vancomycin + meropenem
- D Chloramphenicol IV
Explanation
The presentation is bacterial meningitis in a 6-month-old with sickle cell disease. Gram-negative diplococci in CSF in this age group indicates Neisseria meningitidis. However, sickle cell disease patients are also at high risk for Streptococcus pneumoniae (encapsulated organism). Ceftriaxone 100 mg/kg/day (maximum 4g/day) in 1–2 divided doses is the drug of choice for both meningococcal and pneumococcal meningitis. If penicillin-resistant pneumococcus is suspected, vancomycin is added. Ampicillin-gentamicin is used for neonatal meningitis (Listeria coverage). Chloramphenicol is a historical option no longer first-line.
Reference: Ghai Essential Pediatrics, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.