Prognostic role of serum interleukin-6 levels in polytrauma patients: a comprehensive narrative review

Polytrauma triggers a complex systemic inflammatory response, and early identification of high-risk patients is essential for guiding timely interventions and improving outcomes. Interleukin-6 (IL-6), a rapidly induced proinflammatory cytokine, has emerged as a potential biomarker for prognosis in the trauma setting. This narrative review summarizes current evidence on the prognostic role of IL-6 in polytrauma patients, addressing its biological functions, kinetics after injury, and associations with clinical outcomes such as acute respiratory distress syndrome, multiple organ dysfunction syndrome, intensive care unit admission, and mortality. IL-6 levels have been shown to correlate with injury severity scores and to predict complications more reliably than many other inflammatory markers, largely due to its early elevation and sustained presence in circulation. Furthermore, IL-6 measurement may inform surgical decision-making, particularly in selecting candidates for damage control strategies versus definitive care. Compared to other cytokines and acute-phase reactants, IL-6 demonstrates superior temporal responsiveness and prognostic accuracy in the early postinjury phase. Despite variability in measurement methods and the influence of external confounding factors, IL-6 holds significant promise as a clinical tool for early triage, risk stratification, and potentially therapeutic targeting in trauma care. Standardized protocols and larger multicenter studies are needed to facilitate broader adoption and integration of IL-6 into clinical algorithms.