Cytokine levels (IL-4, IL-6, IL-8 and TGFβ) as potential biomarkers of systemic inflammatory response in trauma patients

Purpose: Much research is now being conducted in order to understand the role of cytokines in the development of the inflammatory response following trauma. The purpose of this study was to evaluate whether serum levels of certain cytokines, measured immediately after initial injury, can be used as potential biomarkers for predicting the development and the degree of severity of the systemic inflammatory response (SIRS) in patients with moderate and severe trauma. Methods We conducted a prospective study with 71 individuals of whom 13 (18.3%) were healthy controls and 58 (81.7%) were traumatized orthopaedic patients who were categorized into two groups: 31 (43.6%) with moderate injuries and 27 (38.1%) patients with severe orthopaedic trauma. Thirty cc of heparinized blood were drawn from each individual within a few hours after the injury. Serum levels of pro-inflammatory, regulatory and anti-inflammatory cytokines were measured in each individual participant. Results High levels of pro-inflammatory cytokines IL-1η,-6,-8,-12, tumour necrosis factor alpha and interferon gamma were found in all injured patients compared to healthy controls. Only IL-6 and IL-8 were significantly higher in the injured patients. Levels of the regulatory cytokines, transformed growth factor beta (TGF-β) and IL-10 were higher in the injured patients, but significant only for TGF-β. Levels of IL-4 were significantly lower in the injured groups as compared to the controls. Conclusions: Secretion of large amounts of pro-inflammatory cytokines and decreased level of anti-inflammatory cytokines during the acute phase of trauma may lead to the development of systemic inflammatory response syndrome (SIRS) in unstable polytraumatized patients. SIRS may result in life threatening conditions as acute respiratory distress syndrome (ARDS) and multiple organ failure (MOF). High levels of IL-6, IL-8, TGFβ and low levels of IL-4 were found to be reliable markers for the existence of immune reactivity in trauma patients. More research is needed to study pattern of cytokine levels along the acute period of injury, after surgical interventions and during recovery.