Association between plasma mitochondrial DNA and sterile systemic inflammatory response syndrome in patients with acute blunt traumatic injury

Background: Plasma mitochondrial DNA (mtDNA) has been associated with the occurrence of systemic inflammatory response syndrome (SIRS), but its relationship to sterile SIRS is unknown. This study was to assess the relationship between plasma mtDNA and sterile SIRS in patients with acute blunt traumatic injury. Methods: This was a prospective study of 65 patients with acute blunt traumatic injury admitted at the Trauma Center of the Army General Hospital (Bejing, China) between April 2010 and April 2013. Demographic and clinical characteristics and injury severity score (ISS) were recorded at admission. Plasma mtDNA, interleukin-6 (IL-6), C-reactive protein (CRP), fibrinogen and white blood cells were measured. Patients were examined regularly for the occurrence of sterile SIRS. Results: Patients who developed sterile SIRS had higher plasma mtDNA levels compared with those who did not develop sterile SIRS (317.6 [97.8-582.3] vs. 238.7 [86.8-591.3] pg/mL, P = 0.005). Pearson correlation analysis showed that plasma mtDNA levels correlated with the ISS score (r = 0.656, P < 0.001). Of the factors, sex (P = 0.005), plasma mtDNA (P = 0.005), CRP (P = 0.003) and fibrinogen (P = 0.012) were the significant predictors for sterile SIRS in univariate analyses. In multivariate analysis showed that plasma mtDNA levels (odds ratio: 1.005, 95% CI: 1.001-1.009, P = 0.011), CRP (odds ratio: 1.089, 95% CI: 1.023-1.107, P = 0.003) and fibrinogen (odds ratio: 1.003, 95% CI: 1.001-1.007, P = 0.046) were independently associated with the occurrence of sterile SIRS. Receiver operating characteristic analysis revealed that using the best cut-off value of 290.0 pg/mL, mtDNA had an AUC of 0.709, specificity of 65% and sensitivity of 80%. Conclusions: Plasma mtDNA levels might be associated with the occurrence of sterile SIRS in patients with acute blunt traumatic injury.