Presepsin in Critical Illness: Current Knowledge and Future Perspectives

The accurate identification of bacterial infections is critical for effective treatment in intensive care units (ICUs), yet current diagnostic methods face limitations in sensitivity and specificity, along-side cost and accessibility issues. Consequently, there's a pressing need for a marker that is economically feasible, rapid, and reliable. Presepsin (PSP), also known as soluble CD14 subtype (sCD14-ST), has emerged as a promising biomarker for early sepsis diagnosis. PSP, derived from soluble CD14, reflects the activation of monocytes/macrophages in response to bacterial infec-tions. It has shown potential as a marker of cellular immune response activation against patho-gens, with plasma concentrations increasing during bacterial infections and decreasing post-antibiotic treatment. Unlike traditional markers such as procalcitonin (PCT) and C-reactive protein (CRP), PSP specifically indicates monocyte/macrophage activation in bacterial infections. While limited studies in critical illness have explored PSP's role in sepsis, its diagnostic accuracy varies with threshold values, impacting sensitivity and specificity. Recent meta-analyses suggest PSP's diagnostic potential for sepsis, yet its standalone effectiveness in ICU infection management remains uncertain. This review provides a comprehensive overview of PSP's utility in ICU set-tings, including its diagnostic accuracy, prognostic value, therapeutic implications, challenges, and future directions.