550 - Early-Onset Sepsis and Antibiotic Exposure Among Infants with Congenital Anomalies

Poster Number: 550
Publication Number: 550.428

Leigh M. Finnegan, Children's Hospital of Philadelphia, Philadelphia, PA, United States; Anne Ades, Childrens Hospital of Philadelphia, Philadelphia, PA, United States; Natalie Rintoul, Children's Hospital of Philadelphia, Philadelphia, PA, United States; Lakshmi Srinivasan, Children's Hospital of Philadelphia, Philadelphia, PA, United States

Background: Early-onset sepsis (EOS) is associated with significant morbidity and mortality. However, in the current era EOS rates are low, and neonatal antibiotic exposure is known to be associated with adverse outcomes. Rates of EOS for infants with complex congenital anomalies are unknown. Cardiorespiratory instability due to underlying condition may be clinically indistinguishable from sepsis, leading to antibiotic initiation.

Objective: We aimed to measure rates of EOS and early antibiotic exposure ( < 72 hours of life) among infants with congenital anomalies born in the Special Delivery Unit (SDU) at the Children’s Hospital of Philadelphia and admitted to the Neonatal Intensive Care Unit (NICU).

Design/Methods: Retrospective study of infants born in the SDU between 2011 and 2020 and admitted to the NICU. EOS was defined as a positive blood culture within 7 days of life associated with antibiotic treatment for >5 days. We analyzed EOS and early antibiotic initiation rates by year. We further categorized the early antibiotic initiation group into those who received short courses (1-3 days of antibiotic exposure within the first week) and long courses (4-7 days). Analysis included summary statistics, Chi-squared analysis, Kruskal-Wallis and Wilcoxon rank sum testing, and Pearson's linear regression.

Results: From 2011-2020, 2513 patients were born in the SDU and admitted to the NICU. There were 10 cases of EOS (0.40%) (Fig. 1). Rates of early antibiotic exposure decreased (p < 0.01), while rates of prematurity, birth weight < 1500g, and pressor, steroid, and ventilator use within the first week did not significantly change (Fig. 2). Those with early antibiotic exposure were more likely to be initiated on steroids, pressors, and invasive ventilation during the first week, and were also more likely to be preterm and weigh < 1500g at birth (Fig. 3), suggesting more severe illness. Early antibiotic exposure was associated with increased 28-day mortality and length of hospital stay (Fig. 3), as was increased severity of illness (p < 0.01).Conclusion(s): Despite low rates of EOS, early antibiotic exposure remains high among newborns with complex congenital anomalies. Prematurity and severity of illness are associated with antibiotic initiation as well as prolonged antibiotic exposure. While rates of prematurity and illness severity remain stable, rates of antibiotic initiation are decreasing. Additional multivariate analyses will further define associations with prematurity, specific diagnoses, and severity of illness, and facilitate development of targeted strategies to decrease unnecessary antibiotic exposure.
Figure 1: Cases of early-onset sepsis from 2011-2020Information on patients diagnosed with EOS from 2011-2020. One patient, whose blood culture grew a bacterium determined to be a contaminant, was excluded.
Figure 2: Rates of Early Antibiotic Exposure, Prematurity, and Illness Severity Markers by YearRates of early antibiotic initiation (initiation of antibiotics within the first 72 hours of life) decreased over the study period, while rates of prematurity, birth weight < 1500g, and pressor, steroid, and antibiotic use within the first week of life did not significantly change.