Role of CSF Presepsin in Critically Ill Patients with Cerebral Damage

Abstract Presepsin (soluble CD14 subtype, sCD14-ST) is an established biomarker of systemic bacterial infection; however, its diagnostic performance in the intrathecal compartment remains insufficiently characterized. In neurocritical care, early diagnosing infection is essential. The study objective is to evaluate cerebrospinal fluid (CSF) presepsin as a potential biomarker of central nervous system (CNS) infections in critically ill patients with external drainage. We conducted a prospective, single-center, observational pilot study (registration number 2024/EK/11102 obtained on april 2024) including 45 adult neurocritical patients between September 2024 and June 2025. CSF samples were collected according to a predefined protocol. Presepsin concentrations were measured using ELISA and correlated with CSF metabolic parameters, such as CSF glucose coefficient, lactate, total protein, and energy balance coefficient. Non-parametric tests and Spearmanꞌs rank correlation analyses were applied. CSF presepsin demonstrated a negative correlation with age ( p = 0,022), positive correlations with serum C-reactive protein ( p = 0,014) and CSF chlorides ( p = 0,038). However, no statistically significant association was observed between CSF presepsin levels and microbiologically confirmed CNS infection. Although higher median presepsin concentrations were noted in infected patients. In neurocritical patients with external CSF drainage, intrathecal presepsin appears to be a promising marker. Hemorrhagic and non-infectious inflammatory processes may confound its diagnostic performance. The study continues with larger, stratified analyses with longitudinal kinetic assessment, which are required to determine the benefits and limitations of CSF presepsin.