701 - Association between early antibiotic exposure after birth and the necrotizing enterocolitis in preterm infants - A Matched Case-Control Study

Publication Number: 701.3611

Robin A. Gatlin, University of Mississippi School of Medicine, Madison, MS, United States; Aubrey Rebentisch, University of Mississippi Medical Center, Atlanta, GA, United States; Md Abu Yusuf Ansari, University of Mississippi Medical Center, Jackson, MS, United States; Padma Garg, University of Mississippi School of Medicine, Jackson, MS, United States; Avinash K. Shetty, Wake Forest University School of Medicine, Winston-Salem, NC, United States; Parvesh Mohan Garg, Wake Forest School of Medicine of Wake Forest Baptist Medical Center, winston salem, NC, United States

Background: In neonates, some studies have demonstrated an increased and as well as decreased risk of NEC with early antibiotics.

Objective: We aim to study the association between early antibiotic exposure duration and necrotizing enterocolitis (NEC) in preterm infants.

Design/Methods: This matched case-control study included infants with NEC (n=97) and matched controls (n= 115) by gestational age (GA) and birth weight, born between 2013 -2020 at University of Mississippi Medical Center. The antibiotic exposure was defined as infants receiving antibiotics = < 3 and >3 days after birth. The association between antibiotic exposure and NEC was analyzed by multivariate regression.

Results: Out of 212 infants included, 103 infants (48.5%) were exposed to antibiotics for < 3 days and 109 infants (51.5%) were exposed to antibiotics >3 days.
Any NEC vs Controls: Infants receiving antibiotics = < 3days, 33 (33/103, 32%) infants had any NEC (Medical 20/33 (60.6%) or 13/33 (39.3%) surgical NEC) and had significantly higher exposure to PIH and longer hospitalization than controls. Infants with surgical NEC had significantly lower birth weight, lower median GA, had higher mortality and longer hospital stay compared to infants with medical NEC and the controls (Table 1).
Those receiving antibiotics >3 days (n=109), 64 cases had any NEC. 34/64 (53%) had medical NEC and the 30/64 (47%) cases had the surgical NEC and had significantly longer hospitalization and the higher mortality than controls.
NEC cohort: 97/212 infants were diagnosed with any NEC. 33/97 (34%) infants received antibiotics 3 days .There was no significant difference between medical and surgical NEC rates (p= 0.62) with respect to antibiotic duration. However, infants exposed to antibiotics >3 days had higher mortality (31% vs 6%; p= 0.011) than those exposed to antibiotics= < 3days. In surgical NEC infants exposed to antibiotics >3 days had later age of NEC onset (18 days [9.25;34.0] vs. 5 days [4.00;19.0]; p=0.002) than other group.
On the multivariate regression analysis, infants receiving antibiotics for >3 days had significantly higher adjusted odds of medical NEC (aOR 2.61,95% CI 1.35 -5.16; p=0.005) and surgical NEC (aOR 3.33, CI 1.57-7.40; p=0.02) than control group ( Table 2). In NEC cohort, those receiving antibiotics for >3 days had higher odds of mortality (OR 7.88,95% CI 1.99- 53.74; p=0.010) than those receiving antibiotics = < 3 days (Table 3).

Conclusion(s): Infants exposed with early antibiotics >3 days after birth were more likely associated with NEC than controls. In NEC cohort, infants exposed to antibiotics >3 days were at greater risk of death.

Table 1: Clinical information in infants receiving antibiotics =< and > 3 days following birth in NEC and control groups
Table 1: Clinical information in infants receiving antibiotics =< and > 3 days following birth in NEC and control groups

Table 2: Association between antibiotic duration (>3 days vs = < 3 days) and severity of NEC using binary logistic regression.
Table 2: Association between antibiotic duration (>3 days vs = < 3 days) and severity of NEC using binary logistic regression.

Table 3 :Association between antibiotic duration (>3 days vs = < 3 days) and severity of NEC among the NEC patients using binary logistic regression.
Table 3: Association between antibiotic duration (>3 days vs = < 3 days) and severity of NEC among the NEC patients using binary logistic regression.

Table 1: Clinical information in infants receiving antibiotics =< and > 3 days following birth in NEC and control groups
Table 1: Clinical information in infants receiving antibiotics =< and > 3 days following birth in NEC and control groups

Table 2: Association between antibiotic duration (>3 days vs = < 3 days) and severity of NEC using binary logistic regression.
Table 2: Association between antibiotic duration (>3 days vs = < 3 days) and severity of NEC using binary logistic regression.

Table 3 :Association between antibiotic duration (>3 days vs = < 3 days) and severity of NEC among the NEC patients using binary logistic regression.
Table 3: Association between antibiotic duration (>3 days vs = < 3 days) and severity of NEC among the NEC patients using binary logistic regression.