Objective: To determine whether commencement of antibiotics within 3 postnatal days in preterm, very low birth weight infants (VLBW, ≤1500 g), is associated with the development of necrotizing enterocolitis (NEC).
Study design: Pre-planned statistical analyses were done to study the association between early antibiotic treatment and later NEC development, using the NEOMUNE-NeoNutriNet cohort of VLBW infants from 13 neonatal intensive care units (NICUs) in five continents (n=2831). NEC incidence was compared between infants who received early antibiotics and those who did not, with statistical adjustments for NICU, gestational age, birth weight, sex, delivery mode, antenatal steroids, Apgar score, and type and initiation of enteral nutrition.
Results: The incidence of NEC was 9.0% in the group of infants who did not receive early antibiotics (n=269) versus 3.9% in the remaining infants (n=2562). NEC incidence remained lower in the early-antibiotic group after stepwise statistical adjustments for NICU (OR 0.57; 95% CI, 0.35-0.94, P < .05) and other potential confounders (OR 0.25; CI, 0.12-0.47, P<0.0001).
Conclusions: In this large international cohort of preterm VLBW infants, a minor proportion of infants did not receive antibiotics just after birth, yet these infants had a higher incidence of NEC. It is important to better understand the role of variables such as time, type, and length of antibiotic treatment on NEC incidence, immune development, gut colonization, and antibiotic resistance in the NICU.