563 - Comparison of Procalcitonin and High Sensitivity C-Reactive Protein as Screening Tests in Infants for Early Onset Sepsis and Late Onset Sepsis

Poster Number: 563
Publication Number: 563.427

Avani Vachhani, LAC+USC Medical Center, LOS ANGELES, CA, United States; Helena Vervaet, Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States; Allison B. Chambliss, Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States; Manuel Durand, Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States; Lorayne Barton, LAC+USC Med Ctr, Los Angeles, CA, United States; Rangasamy Ramanathan, Keck School of Medicine of USC, Los Angeles, CA, United States; Rowena G. Cayabyab, LAC+USC MEDICAL CENTER, LOS ANGELES, CA, United States

Background: Early detection of both early onset sepsis (EOS) and late onset sepsis (LOS) in newborns is difficult as the early signs of infection are often nonspecific. A laboratory test to rapidly identify these infants would add value in improving outcomes and limiting unnecessary antibiotic exposure.

Objective: The purpose of this study was to compare the utility of procalcitonin (PCT) and high sensitivity C-reactive protein (hsCRP) as screening tests for EOS and LOS.

Design/Methods: Retrospective study of infants admitted to the neonatal intensive care unit from August 2018-February 2021. Infants with at least one paired PCT and hsCRP values obtained and with blood, urine or cerebrospinal fluid (CSF) culture results were included. EOS workup was performed at <72 hours of life while LOS workup at >72 hours of life. Infants on antibiotics at the time of workup and those diagnosed with presumed infection, but negative cultures were excluded. Infants were classified as non-infected or infected (positive culture). EOS results were analyzed in time interval as follows; 0-12 hours of life and 13-24 hours of life. Data were analyzed with Fisher-exact test and Wilcoxon rank sum where appropriate. Diagnostic value was determined by calculating sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Cutoff of 10 mg/L for hsCRP and 0.5 ng/mL and 1.0 ng/mL for PCT were used for EOS based on published literature. Cutoff of 20 mg/L for hsCRP and 0.5 ng/mL and 1.0 ng/mL were used for LOS based on AAP recommendation.

Results: A total of 459 infants received workups and met inclusion criteria for EOS and 101 infants for LOS. There were 12 infants (3%) who had confirmed EOS while 21 (17%) with confirmed LOS. Demographics and outcomes of infants are shown in Table 1. The sensitivity, specificity, PPV and NPV for serial measurements of PCT and hsCRP are shown in Table 2. For EOS, subsequent measurements of both biomarkers led to an increase in sensitivity, but a decrease in PPV while in LOS sensitivity and PPV increased. The areas under the ROC curve were higher for both biomarkers for LOS in comparison to EOS (Table 2).Conclusion(s): Our preliminary findings indicate that PCT and hsCRP may have better diagnostic value in patients screened for LOS in comparison to EOS. Previous studies suggest a natural rise in levels on serial measurements in the first 72 hours in neonates influencing its diagnostic value and presence of peripartum and maternal risk factors can also influence levels after birth in the absence of infection.
Table 1: Demographics Between Groups+ Mean ± SD
*Median (Interquartile range)
^ Some missing data in LOS patients
Note: variables for LOS counted once if admitted for multiple LOS workups
Table 2: Comparison of Biomarkers