BACKGROUND: Early-life antibiotic exposure is disproportionately high compared to the burden of culture-proven early-onset sepsis (CP-EOS). We assessed the contribution of culture-negative cases to the overall antibiotic exposure in the first postnatal week. METHODS: We conducted a retrospective analysis across eleven countries in Europe, North America, and Australia. All late-preterm and term infants born between 2014 and 2018 who received intravenous antibiotics during the first postnatal week were classified as culture-negative cases treated for ≥5 days (CN ≥ 5d), culture-negative cases treated for <5 days (CN < 5d), or CP-EOS cases. RESULTS: Out of 757,979 infants, 21,703 (2.9%) received intravenous antibiotics. The number of infants classified as CN ≥ 5d, CN < 5d, and CP-EOS was 7996 (37%), 13,330 (61%), and 375 (1.7%). The incidence of CN ≥ 5d, CN < 5d, and CP-EOS was 10.6 (95% CI 10.3-10.8), 17.6 (95% CI 17.3-17.9), and 0.49 (95% CI 0.44-0.54) cases per 1000 livebirths. The median (IQR) number of antibiotic days administered for CN ≥ 5d, CN < 5d, and CP-EOS was 77 (77-78), 53 (52-53), and 5 (5-5) per 1000 livebirths. CONCLUSIONS: CN ≥ 5d substantially contributed to the overall antibiotic exposure, and was 21-fold more frequent than CP-EOS. Antimicrobial stewardship programs should focus on shortening antibiotic treatment for culture-negative cases. IMPACT: In a study of 757,979 infants born in high-income countries, we report a presumed culture-negative early-onset sepsis incidence of 10.6/1000 livebirths with an associated antibiotic exposure of 77 antibiotic days per 1000 livebirths. This study sheds light on the major contribution of presumed culture-negative early-onset sepsis to early-life antibiotic exposure. Given the diagnostic uncertainty surrounding culture-negative early-onset sepsis, the low mortality rate, and the disproportionate antibiotic exposure associated with this condition, our study emphasizes the importance of targeting culture-negative early-onset sepsis in antimicrobial stewardship programs.

• MeSH
• antibakteriální látky * terapeutické užití   aplikace a dávkování   MeSH
• incidence MeSH
• lidé MeSH
• novorozenec nedonošený MeSH
• novorozenec MeSH
• novorozenecká sepse * farmakoterapie   diagnóza   MeSH
• retrospektivní studie MeSH
• sepse * farmakoterapie   epidemiologie   diagnóza   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• Geografické názvy
• Austrálie MeSH
• Evropa MeSH
• Severní Amerika MeSH

IMPORTANCE: Appropriate use of antibiotics is life-saving in neonatal early-onset sepsis (EOS), but overuse of antibiotics is associated with antimicrobial resistance and long-term adverse outcomes. Large international studies quantifying early-life antibiotic exposure along with EOS incidence are needed to provide a basis for future interventions aimed at safely reducing neonatal antibiotic exposure. OBJECTIVE: To compare early postnatal exposure to antibiotics, incidence of EOS, and mortality among different networks in high-income countries. DESIGN, SETTING, AND PARTICIPANTS: This is a retrospective, cross-sectional study of late-preterm and full-term neonates born between January 1, 2014, and December 31, 2018, in 13 hospital-based or population-based networks from 11 countries in Europe and North America and Australia. The study included all infants born alive at a gestational age greater than or equal to 34 weeks in the participating networks. Data were analyzed from October 2021 to March 2022. EXPOSURES: Exposure to antibiotics started in the first postnatal week. MAIN OUTCOMES AND MEASURES: The main outcomes were the proportion of late-preterm and full-term neonates receiving intravenous antibiotics, the duration of antibiotic treatment, the incidence of culture-proven EOS, and all-cause and EOS-associated mortality. RESULTS: A total of 757 979 late-preterm and full-term neonates were born in the participating networks during the study period; 21 703 neonates (2.86%; 95% CI, 2.83%-2.90%), including 12 886 boys (59.4%) with a median (IQR) gestational age of 39 (36-40) weeks and median (IQR) birth weight of 3250 (2750-3750) g, received intravenous antibiotics during the first postnatal week. The proportion of neonates started on antibiotics ranged from 1.18% to 12.45% among networks. The median (IQR) duration of treatment was 9 (7-14) days for neonates with EOS and 4 (3-6) days for those without EOS. This led to an antibiotic exposure of 135 days per 1000 live births (range across networks, 54-491 days per 1000 live births). The incidence of EOS was 0.49 cases per 1000 live births (range, 0.18-1.45 cases per 1000 live births). EOS-associated mortality was 3.20% (12 of 375 neonates; range, 0.00%-12.00%). For each case of EOS, 58 neonates were started on antibiotics and 273 antibiotic days were administered. CONCLUSIONS AND RELEVANCE: The findings of this study suggest that antibiotic exposure during the first postnatal week is disproportionate compared with the burden of EOS and that there are wide (up to 9-fold) variations internationally. This study defined a set of indicators reporting on both dimensions to facilitate benchmarking and future interventions aimed at safely reducing antibiotic exposure in early life.

• MeSH
• antibakteriální látky terapeutické užití   MeSH
• kojenec MeSH
• lidé MeSH
• novorozenec MeSH
• novorozenecká sepse * farmakoterapie   epidemiologie   MeSH
• průřezové studie MeSH
• retrospektivní studie MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Austrálie MeSH
• Severní Amerika MeSH