Neonatal Early Onset Sepsis: Impact of Kaiser Calculator in an Italian Tertiary Perinatal Center

Background: Suspected early-onset sepsis (EOS) results in antibiotic treatment and blood withdraw of a substantial number of neonates who are uninfected. We evaluated if the EOS calculator can reduce antibiotic exposure and invasive procedures for suspected EOS in term and late preterm neonates, without any significant increase in adverse outcomes. Methods: The proportion of EOS risk in neonates >= 35 weeks gestation exposed to antibiotics, intensive monitoring and blood withdrawal was compared between a baseline period (January 2018-May 2018), when Centers for Disease Control guidelines approach was used, and a post-EOS calculator-implementation period (June 2018-December 2019). Results: We included 4363 newborn infants with gestational age >= 35 weeks, respectively 824 in baseline period and 3539 in the EOS calculator period. Among them, 1021 (23.4%) infants presented risk factors for neonatal sepsis. There was a halving in empirical antibiotics exposure: 3% in the baseline and 1.4% in the post-EOS-implementation period, P < 0.05. Blood culture and laboratory evaluations had fallen from 30.6% to 15.4% (P < 0.05). Close monitoring of vital parameters decreased from 25.4% to 4.8% (P < 0.05). The number of antibiotic days per 100 live births decreased from 15.05 to 6.36 days (P <0.05). The incidence of culture-confirmed sepsis and clinical sepsis was very low in 2 periods. Only one infant identified at low-risk by Kaiser calculator at birth developed symptoms after 12 h from birth. We had no readmissions for EOS. Conclusions: Application of the EOS calculator more than halved the burden of intensive monitoring and antibiotic exposure, without compromising safety in a population with a relatively low incidence of culture-proven EOS and good access to follow-up care.