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Assessment and Evaluation of the High Risk Neonate: The NICU Network Neurobehavioral Scale
Published on: August 25, 2014
Neurodevelopmental Outcome after Late-Onset Bacterial Sepsis in Infants Born before 29 Weeks' Gestation
Smita Roychoudhury1, Abhay Lodha2,3, Anne Synnes4
1Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada.
American Journal of Perinatology
|January 29, 2026
Summary
Late-onset sepsis in preterm infants increases mortality and neurodevelopmental impairment risk. Gram-negative and mixed sepsis pose the highest risks for adverse outcomes in extremely preterm infants.
Area of Science:
- Neonatalogy
- Pediatric Neurology
- Infectious Diseases
Background:
- Late-onset sepsis (LOS) significantly impacts mortality and long-term outcomes in preterm infants.
- Understanding the specific risks associated with different bacterial pathogens is crucial for targeted interventions.
- Limited data exists on neurodevelopmental (ND) outcomes stratified by causative bacteria in extremely preterm infants.
Purpose of the Study:
- To evaluate neurodevelopmental outcomes at 18-24 months corrected age in preterm infants (<29 weeks gestation) with LOS.
- To compare ND outcomes based on the type of bacterial pathogen (Gram-positive, Gram-negative, mixed) causing LOS.
- To identify specific bacterial types associated with increased risk of death or neurodevelopmental impairment.
Main Methods:
- Retrospective cohort study of non-anomalous infants born <29 weeks gestation in Canadian NICUs (2010-2017).
- Included infants with ND assessments at 18-24 months corrected age through the Canadian Neonatal Follow-Up Network.
- Compared ND outcomes (death or neurodevelopmental impairment) between infants with LOS (categorized by pathogen type) and those without sepsis, using adjusted analyses.
Main Results:
- Of 3,640 infants, 823 (22.6%) developed LOS. Gram-positive sepsis was most common (69.1%), followed by Gram-negative (20.9%) and mixed (10%).
- Infants with LOS had significantly lower birth weight, gestational age, and higher rates of neonatal morbidities.
- Gram-negative sepsis (aOR=1.80) and mixed sepsis (aOR=2.38) were significantly associated with higher odds of death or neurodevelopmental impairment compared to no sepsis.
Conclusions:
- Late-onset bacterial sepsis, especially Gram-negative and mixed types, increases the risk of death or neurodevelopmental impairment in extremely preterm infants.
- These findings highlight the critical need for early identification and management of LOS in this vulnerable population.
- Pathogen-specific risks underscore the importance of tailored treatment strategies to improve long-term neurodevelopmental outcomes.
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