High mobility group box-1 expression correlates with poor outcome in lung injury patients

Chest trauma is frequently followed by pulmonary contusion and sepsis. High mobility group box-1 (HMGB-1) is a late mediator of severe sepsis that has been associated with mortality under experimental conditions. We studied HMGB-1 mRNA expression in patients with lung injury and its relationship with the severity of trauma and survival.A total of 24 consecutive patients with chest trauma referring to the Intensive Care Unit of Messina University Hospital, were enrolled. Lung trauma was established on the basis of chest X-ray and computed tomography. Injury Severity Score (ISS), Revised Trauma Score (RTS) and Glasgow Coma Scale (GCS) were also assessed. Accordingly to these results 6 patients were considered as controls because of no penetrating trauma and low ISS.Blood and broncho-alveolar lavage fluid (BALF) from chest trauma patients were withdrawn at admission and 24 h after the beginning of the standard therapeutic protocol.HMGB-1 mRNA increased significantly in blood (r = 0.84) and BALF (r = 0.87) from patients with trauma and pulmonary contusion and positively correlated with the severity of trauma (based on ISS and RTS) and the final outcome. HMGB-1 protein levels were also elevated in BALF macrophages from severe trauma patients compared to control subjects, furthermore TNF-α and its receptor TNFR-1 mRNA levels were also markedly increased in patients with a poor outcome respect to other subjects.Our study suggests that HMGB-1 may be an early indicator of poor clinical outcome in patients with chest trauma.