705 - Incidence and Outcomes of Recurrent Necrotizing Enterocolitis in Preterm Neonates: A Retrospective Cohort Study

Publication Number: 1682.705

Doaa Al-Dweik, The University of Western Ontario - Schulich School of Medicine & Dentistry, London, ON, Canada; Dwayne Mascarenhas, The Hospital for Sick Children, Toronto, ON, Canada; Ujjwala Mantha, University of Toronto Temerty Faculty of Medicine, Toronto, ON, Canada; Shravan Kanaparthi, The Hospital for Sick Children, Toronto, ON, Canada; Mary Woodward, Hospital for Sick Children, Toronto, ON, Canada; Bonny Jasani, The Hospital for Sick Children, Toronto, ON, Canada

Background: Necrotizing enterocolitis (NEC) is one of the most common GI emergencies in neonates and is associated with significant mortality and morbidity. Although recurrent NEC has been reported in neonates, data on its incidence, risk factors and clinical outcomes remain limited. The aim of this study is to evaluate the incidence, risk factors and clinical outcomes of recurrent NEC in preterm infants.

Objective: Incidence and potential risk factors of NEC recurrence among preterm infants with NEC.
Comparison of short-term outcomes of recurrent NEC with single episode NEC in preterm infants.

Design/Methods: We conducted a retrospective cohort study of preterm infants with confirmed NEC (Bell's stage ≥ II) admitted to a single quaternary NICU between January 2018 and December 2023. Infants with spontaneous intestinal perforation or enterocolitis secondary to Hirschsprung's disease or other GI surgical conditions were excluded. Preterm infants with recurrent NEC (defined as >1 episode of NEC) were compared with those with single episode. Demographical, perinatal, radiological, operative, and clinical outcome data were extracted from electronic records.
Categorical variables were expressed as frequencies and percentages, while continuous variables were summarized as mean ± standard deviation or median with interquartile range. Group comparisons were performed using the Student t-test or Mann-Whitney U test for continuous variables, and Fisher's exact or Chi-square test for categorical variables. Variables significant on univariate analysis were entered into a multivariable logistic regression model to evaluate the association between recurrent NEC and adverse outcomes.

Results: A total of 225 preterm infants were diagnosed with confirmed NEC. Among them, 27 infants (12%) experienced recurrence. No significant risk factors were identified (Table 1). In the adjusted analysis, infants with recurrent NEC had significantly longer hospital stays, prolonged time to achieve full feeds and longer duration of parenteral nutrition. They also demonstrated higher peak conjugated bilirubin levels and an increased incidence of PNALD (Table 2).

Conclusion(s): Data from our center demonstrates a 12% recurrence rate among preterm infants with confirmed NEC, with no identifiable risk factors for recurrence. Recurrent NEC was associated with significant adverse effects on nutritional outcomes and extended hospitalization. These findings highlight the clinical burden of recurrent NEC and underscore the need for further research to elucidate underlying mechanisms, optimize post-NEC feeding strategies and improve outcomes in this population.

Figure 1: Comparison of Basic Characteristics between NEC recurrence group and Single Episode NEC group.


Figure 2: Comparison of Mortality, Cardio-respiratory, Common Neonatal Morbidities, Nutritional and Growth Outcomes between NEC Recurrence Group and Single Episode NEC Group.


Figure 3: Association Between Recurrent NEC and Pre-specified Neonatal Outcomes.