LAUSR

Learning Objectives: Gram-positive (GP) and gram-negative (GN) bacteria activate different Toll-like receptors signaling pathways resulting in production of different proinflammatory cytokines that stimulate procalcitonin (PCT) release. Adult data suggests median PCT values are higher in GN infections compared to GP, yet there is limited data on whether PCT can differentiate between GP and GN infections in pediatric ICU patients. The aim of this study was to evaluate whether PCT can discriminate infections caused by GP and GN organisms in a PICU cohort. Methods: This was a single-center, retrospective medical record review. All patients with documented infections with a single organism from a sterile site (blood, CSF, urine, BAL, tissue) and PCT levels from January 2013 to December 2017 were eligible for inclusion. During this time period, there was no standard protocol for obtaining PCT levels and patients with polymicrobial infections were excluded. All analyses were performed using IBM SPSS Version 24 (SPSS Inc., Chicago, IL). Results: 54 patients, 31 males and 23 females, with documented growth of a pathogen from a sterile source were included. The median age in the GN group was 10 months (IQR 3 months-7 years) compared with 5.5 months (IQR 2 months-3 years) in the GP group, p = 0.35. The median weight was 10 kg (IQR 4.9–20.4 kg) in the GN group compared with 7.6 kg (IQR 3.7–15 kg) in the GP group, p = 0.2. The median PRISM score was 14 (IQR 9–20) in the GN group compared with 15 (IQR 8–24) in the GP group, p = 0.42. The median PCT in the GN group was 7.74 ng/mL (IQR 0.7–22.4) vs 4.28 ng/mL (IQR 0.8–22.3) in the GP group, p = 0.61. Conclusions: This preliminary data from a PICU cohort suggests the elevation in PCT is similar whether the causative organisms is a GP or GN organism.