A neonate born at 36 weeks gestation presents on day 3 with temperature instability, poor feeding, respiratory distress, and bulging anterior fontanelle. CSF shows: WBC 120 cells/mm³ (80% PMN), glucose 18 mg/dL, protein 320 mg/dL, Gram-positive diplococci on Gram stain. The most appropriate antibiotic regimen is:

• A IV ampicillin + gentamicin
• B IV cefotaxime + ampicillin ✓
• C IV vancomycin + cefotaxime
• D IV meropenem + vancomycin

Explanation

Gram-positive diplococci with CSF pleocytosis and hypoglycorrhachia in a neonate suggest Streptococcus agalactiae (Group B Streptococcus) meningitis, the most common cause of bacterial meningitis in neonates. The standard regimen for neonatal meningitis due to GBS is IV ampicillin + cefotaxime (or ampicillin + gentamicin for sepsis without meningitis). Cefotaxime achieves superior CSF penetration compared to gentamicin and is preferred when meningitis is present. Vancomycin + cefotaxime would be reserved for late-onset sepsis with possible nosocomial MRSA. Meropenem + vancomycin is reserved for resistant organisms. Ampicillin alone is insufficient for meningitis.

Reference: Ghai Essential Pediatrics, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.