The strong correlation between neonatal early-onset Group B Streptococcal disease and necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a leading cause of newborn gastrointestinal emergencies, affecting 1-3 per 1000 live births. Although NEC has been linked to a microbial etiology, associations with maternal intrapartum and resultant newborn early-onset invasive Group B streptococcus (EO-GBS) have been weakly defined.

The study aim was to determine the relationship between EO-GBS and NEC.

Data from 2008 to 2015 were collected from pediatric records with ICD diagnosis codes consistent with all stages of NEC, with the exception of neonatal EO-GBS data (only available 2011-2015).

For the 131 newborns meeting inclusion criteria, the mean gestational age (GA) and birthweight at delivery was 30.2 weeks and 1449 g. Maternal comorbidities were not associated with a more advanced stage of NEC, however male gender (OR 3.2, p < .001), lower mean 1 (OR = 0.89, p = .045) and 5 min Apgar scores (OR = 0.84, p = .009) were significantly associated with higher NEC stage, after controlling for GA. Infectious morbidities including chorioamnionitis (OR = 1.5, p = .553) and intrapartum antibiotic administration (OR = 1.3, p = .524) were not significantly associated with higher NEC stage. Neither neonatal sepsis workup (OR = 0.27, p = .060) nor positive blood culture (OR = 0.97, p = .942) prior to NEC diagnosis were statistically significant. Type of feed prior to diagnosis (p = .530) was not significantly associated with NEC stage, however, expressed breast milk tended to be protective against higher stage of NEC (OR = 0.49, p = .055). Type of feed included total parenteral nutrition, mother's or donor expressed breast milk, trophic, full and high calorie feeds. Of the 579 newborns admitted from 2011 to 2015, 13 (2%) were diagnosed with EO-GBS and 64 met diagnostic criteria for NEC. GBS positive newborns had significantly higher odds of NEC (OR = 5.37, p = .009). NEC stage was not significantly different for patients with GBS positive vs. GBS negative mothers (p = .732), nor was there a significant difference in GA (p = .161).

Our study is the first to describe a strong correlation between neonatal EO- GBS disease and NEC, with more than a five-fold increase in the odds of developing NEC in newborns of GBS positive mothers.

To investigate a possible relationship between EO-GBS disease and the neonatal diagnosis of NEC. Secondary analysis will determine if maternal antepartum and intrapartum factors along with neonatal variables contribute to a more advanced stage of NEC by retrospective chart review of patient data collected at Children's Hospital: New Orleans.