A 4-month-old infant is brought with high fever (39.5°C), irritability, and a bulging anterior fontanelle. CSF analysis shows: turbid fluid, WBC 2000 cells/mm3 (90% neutrophils), protein 180 mg/dL, glucose 20 mg/dL (blood glucose 90 mg/dL). Gram stain shows Gram-positive cocci in pairs. Which antibiotic is the drug of choice for this condition?
- A Ampicillin
- B Ceftriaxone ✓
- C Vancomycin
- D Chloramphenicol
Correct answer: B. Ceftriaxone
Explanation
The CSF findings confirm bacterial meningitis (neutrophilic pleocytosis, high protein, very low glucose ratio). Gram-positive cocci in pairs at 4 months of age indicate Streptococcus pneumoniae (pneumococcus). Third-generation cephalosporins like ceftriaxone or cefotaxime are the current drugs of choice for pneumococcal meningitis, providing excellent CNS penetration. Dexamethasone is given adjunctively to reduce neurological sequelae, particularly sensorineural hearing loss. Vancomycin is added if penicillin/cephalosporin resistance is suspected.
Reference: Ghai Essential Pediatrics, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.