Neonatal Nasopharyngeal Colonization with Group B Streptococcus and its Association with Clinical Sepsis.

Objective This study aims to determine whether nasopharyngeal (NP) colonization with group B streptococcus (GBS) is associated with early-onset clinical sepsis within 72 hours of birth, prolonged antibiotic duration, longer neonatal intensive care unit (NICU) stay, and delay in tolerating full feeds among neonates ≥ 35 weeks gestation. Study Design A retrospective cohort study of 192 NICU neonates admitted for sepsis evaluation. Based on their GBS colonization status, the mother-neonate pairs were divided into four groups of mother-negative neonate (baby)-positive (MNBP), mother-positive neonate-positive (MPBP), mother-positive neonate-negative (MPBN), and a reference group of mother-negative neonate-negative (MNBN). Neonates with GBS-positive blood cultures were excluded. Results The colonized neonate groups of MNBP (odds ratio [OR]: 21.8, 95% confidence interval [CI]: 7.99, 59.44) and MPBP (OR: 35.5, 95% CI: 9.57, 131.70) were each associated with increased odds for clinical sepsis (p < 0.001). A similar pattern occurred for prolonged antibiotic use. MPBP group was associated with the increased NICU stay (adjusted β: 0.1, standard error = 0.05, p < 0.01). None of the GBS groups were associated with increased days to full feeds. Conclusion Neonatal NP GBS colonization was found among a substantial proportion of GBS-negative mothers and was associated with an increased diagnosis of clinical sepsis.