Clinical and Laboratory Parameters as Biomarkers for Diagnosis and Prognosis of Sepsis in Patients Admitted to Intensive Care Units

Abstract

The Intensive Care Unit (ICU) has the highest incidence of patients with various infectious processes. Sepsis, a systemic inflammatory response syndrome associated with infections, is characterized by inflammatory cytokine production, innate immune system activation, mitochondrial damage, and severe organ dysfunction. Early diagnosis is crucial for appropriate therapeutic interventions and reducing mortality. Various biomarkers have been studied for diagnostic and prognostic purposes, including lactate, interleukins, C-reactive protein, and procalcitonin. Immune-inflammatory biomarkers, such as leukogram, leukocyte ratios, neutrophil variation index, and leukocyte morphological parameters, provide valuable information about sepsis severity and progression. Additionally, redox state and cellular stress response biomarkers contribute to understanding sepsis pathophysiology and organ dysfunction stratification. The combined use of these biomarkers allows for more accurate diagnoses, early treatment, reduced hospital stays, minimized sequelae, and decreased sepsis mortality risk. This chapter describes the applicability of clinical and laboratory parameters as biomarkers for diagnosing and prognosing infectious processes and sepsis in ICU patients.