Sepsis and Antibiotics in Extremely Preterm Infants: Early Empirical Treatment Was Common, While Late‐Onset Sepsis Accounted for Most Cases and Antibiotic Use

AIM: The aim was to investigate the incidence of sepsis and use of antibiotics among extremely preterm infants, given the limited number of population-based studies examining this. METHODS: This retrospective study in Eastern Denmark included all liveborn infants from 23 + 0 weeks/days to 27 + 6 weeks/days of gestation from 2019 to 21. Data on dispensed intravenous antibiotics were obtained from the regional joint electronic health platform. Early-onset sepsis was defined as occurring within the first 72 h of life and late-onset sepsis from 3 to 90 days. Positive blood culture episodes were classified as proven sepsis. RESULTS: Within the first six months of life, 187 of the 232 (81%) infants received intravenous antibiotics. Empirical treatment was initiated for early-onset sepsis in 164 of the 232 infants (71%) and late-onset sepsis in 118 (51%). Late-onset sepsis accounted for 90% of proven sepsis, predominantly caused by Staphylococcus aureus and Coagulase-negative Staphylococcus. Antibiotic use for late-onset sepsis was three-fold higher than for early-onset sepsis (9902 versus 3413 days per 1000 live births). Sepsis caused two deaths (9 per 1000 live births infants). CONCLUSION: Suspected early-onset sepsis was the most common indication for antibiotic initiation, but late-onset accounted for most proven sepsis episodes and antibiotic exposure in extremely preterm infants.