Neonatal Group B Streptococcus sepsis with negative maternal screening: a case report

BACKGROUND: Group B Streptococcus (GBS) is a leading cause of early-onset neonatal sepsis (EOS). Intrapartum antibiotic prophylaxis (IAP) based on maternal GBS screening significantly reduces the incidence of neonatal GBS disease. CASE PRESENTATION: We report a term neonate who developed early-onset GBS sepsis and meningitis despite a negative maternal GBS screening result obtained at 39 weeks of gestation. The infant presented with respiratory distress, poor feeding, and hypotonia shortly after birth. Blood culture confirmed GBS bacteremia, and cerebrospinal fluid (CSF) analysis supported concurrent meningitis. He was successfully treated with intravenous antibiotics, initially with penicillin and ceftazidime, then escalated to vancomycin for better central nervous system penetration following meningitis diagnosis, before de-escalation back to penicillin. Total antibiotic duration was 17 days. Cranial imaging revealed small hemorrhagic foci in the left centrum semiovale and periventricular area, which resolved on follow-up MRI. CONCLUSIONS: This case highlights the potential for false-negative maternal GBS screening and underscores the importance of clinical vigilance. Empirical antibiotic therapy for suspected neonatal sepsis should be considered based on clinical presentation, even when maternal screening is negative.