Use of a Modified Early-Onset Sepsis Risk Calculator for Neonates Exposed to Chorioamnionitis.

Objective To validate the recently modified Kaiser Permanente early-onset sepsis (EOS) calculator with a higher baseline incidence in chorioamnionitis exposed neonates. Study design This is a retrospective study of chorioamnionitis-exposed neonates born at >= 35 weeks of gestation with a known EOS incidence of 4.3/1000. The risk and management categories were calculated using the calculator with an incidence of 4/1000. The results were compared with a previous analysis of the same cohort that used an EOS incidence of 0.5/1000. Results In our sample, the EOS calculator recommends at least a blood culture in 834 of 896 (93.1 %) and empiric antibiotics in 533 of 896 (59.5%) chorioamnionitis-exposed neonates when using an EOS incidence of 4/1000. This captures 5 of 5 neonates (100%) with EOS. When using a baseline EOS incidence of 0.5/1000, the calculator recommends at least a blood culture in only 289 of 896 (32.2%) and empiric antibiotics in only 209 of 896 (23.3%) neonates, but fails to recommend empiric antibiotics in 2 of 5 neonates with EOS (40%). Conclusions When using an EOS risk of 4 of 1000 in infants exposed to mothers with chorioamnionitis, the EOS calculator has the ability to capture an increased number of neonates with culture-positive EOS. However, this change also leads to nearly a 3-fold increase in the use of empiric antibiotics and an evaluation with blood culture in almost all infants born to mothers with chorioamnionitis.