The usability of umbilical cord blood and infant blood procalcitonin as an early diagnostic marker in diagnosing early onset bacterial sepsis to enhance antibiotic stewardship (A prospective, case-control study).

Abstract

Objective: The aim of this study is to investigate if umbilical cord blood and infant blood procalcitonin could be useful to distinguish infected from healthy newborns with or without early onset bacterial sepsis (EOS) risk factors.

Patients and methods: This prospective case control study was done at Al-Azhar University Hospitals pediatric and neonatology departments (Alhussain, Alzahraa & Assiut branches), Helwan and Luxor University Hospitals during a period started from January 2023 to July 2023. Proclcitonin (PCT) was examined in umbilical cord blood from neonates that were 32 weeks or older at birth and after 24 hours after birth (Del PCT). Groups had the following definitions among the subjects: 1) EOS that was confirmed by culture; (n=20) 2) EOS that might occur based on risk factors for which antibiotics were given for less than 72 hours; (n =20) 3) risk factor(s) for EOS that could occur with no given antibiotic therapy; (n=20) 4) Healthy controls (n = 100). In addition, if taking blood was required for routine treatment, tests for C-reactive protein (CRP) and PCT were performed on venous or capillary blood.

Results: Umbilical cord blood PCT levels were significantly higher in samples of group 1 compared to other groups. The cut-off of the umbilical cord CRP was 10.5 mg/L, the sensitivity, specificity, PPV and NPV were 41, 88.0, 29 and 28%, respectively. At a PCT cut-off of 1.18 ng/mL, the sensitivity, specificity, PPV and NPV were 79, 91, 51 and 61%, respectively.

Conclusion: Neonates ≥32 weeks with a confirmed or probable EOS had higher umbilical cord blood PCT levels, but those with EOS risk factors have lower levels. However, PCT does not appear to be a good indicator following antibiotic therapy for the mother. So, to differentiate between healthy and infected neonates with or without EOS risk factors, PCT may be helpful.