84 Looking back to move forward; can fetal placental inflammatory response play a role in risk of sepsis and clinical decision making in preterm infant

Abstract

Abstract Primary Subject area Neonatal-Perinatal Medicine Background Sepsis adversely impacts the survival of very low birth weight infants (VLBW), with a mortality risk up to 50%. Its diagnosis in premature infants is challenging. Conversely, prolonged antibiotic use is associated with perilous potential consequences, propelling the need to better identify those at risk of sepsis. The presence of a histological intra-amniotic inflammation (IAI) response may be associated with an increased risk of early onset sepsis (EOS). Currently, it is unknown how the diagnosis of histological IAI impacts the risk of sepsis. Objectives Our research goal is to explore histological fetal and maternal inflammation in the placenta in VLBW infants and to evaluate if specific recommendations about antibiotic management of VLBW infants with histological fetal response can be proposed. Design/Methods Retrospective cohort study of all infants < 1500 g born to a mother with histologically confirmed IAI. Demographic information about the pregnancy, delivery and postnatal course up to 28 days of life was extracted. Descriptive statistical analysis was conducted to compare the characteristics of infants with histological fetal response using χ2 test or Fisher’s exact test and Wilcoxon rank sum test or ANOVA. Results Seventy-three mother-baby pairs were reviewed. EOS prevalence (19%) in our IAI group of VLBW infants is much higher than EOS observed in all VLBW infants from the Canadian Neonatal Network database (below 3%). In our cohort, the majority had fetal inflammatory stage 1 (31.6%) and fetal inflammatory grade 0 (50%). There was no statistically significant distribution amongst the fetal stages or grades. Time to sepsis event analysis showed that the earlier fetal inflammatory grade was associated with positive cultures occurring earlier, while in the later grades there demonstrated longer latency to positive cultures. This trend was also true when looking at the maternal inflammatory stages. Nine infants who had antibiotics discontinued from day of life (DOL) 2-5 developed a positive blood culture ≤ DOL8. Conclusion Our results suggest that the presence of mild fetal inflammatory changes is associated with earlier positive cultures. We hypothesize that later grades may be associated with longer infection exposure leading to prolonged maternal antibiotics, resulting in less EOS. Majority of positive cultures were within the 3-8 day window, suggesting a role of knowing the fetal inflammatory response when deciding duration of antibiotic treatment.