56: Culture-Positive Neonatal Sepsis in a Level II Nursery

Abstract

Background: The incidence of 'early-onset neonatal sepsis' (EONS) has significantly declined in North America following the implementation of guidelines for intrapartum antibiotic prophylaxis for Group B streptococcus, but the Canadian rates of EONS are not well defined. Each year, approximately 600 newborns are admitted to our Level II Intermediate Nursery (IN), of whom many receive antibiotics for 'rule out sepsis'. However the incidence of culture-proven EONS and the distribution of pathogenic bacteria in this population is presently not well defined. Objectives: The primary purpose of this study is to determine the incidence of culture-positive blood infections in infants admitted to the Level II Intermediate Nursery (IN). Secondary aims will be to characterize patterns of bacterial susceptibility, specifically to the antibiotics that are currently used to treat neonatal sepsis in the IN. Design/Methods: In this study, blood cultures from neonates admitted to the Level II nursery over a three-year period from 2007 to 2009 were retrospectively reviewed. Ethical approval was obtained prior to data collection. Admission criteria were: >33 weeks gestation, birth weight >1500 g, mild to moderate respiratory distress, infants requiring IV fluid, infants at risk for abnormal transition, cord pH <7.0, and infants with congenital anomalies requiring observation. We excluded infants admitted from other hospitals and infants transferred to the Intermediate Nursery from the Level III NICU. Charts for infants with positive blood cultures were evaluated for clinical signs and symptoms of sepsis using our centres established sepsis protocol. The incidence of EONS was determined, and the offending bacterial pathogens were characterized. Results: A total of 733 blood cultures were reviewed during the threeyear period, of which 12 were positive for bacterial growth. Six were identified as contaminants based on species and clinical manifestation. The overall incidence of EONS was found to be between 0.4% to 1.3% of cultured patients, with the most common organisms being coagulase-negative Staphylococci, followed by Streptococcus agalactiae. All clinically significant isolates were sensitive to ampicillin and gentamycin. Conclusions: The incidence of culture positive EONS in a cohort of neonates >33 weeks' gestation at a major Canadian level II nursery is extremely low. In light of these findings future work will focus on further characterizing risk factors for true EONS, with a view to reducing the number of infants, at potential risk, who receive empiric antibiotics in the first days of life. This would have positive implications for the burden of care of IV antibiotic administration, as well as financial savings and benefits for the gut microbiome.