In a ROC analysis to distinguish between patients with noninfectious SIRS and patients with sepsis/severe sepsis, IL-6, LBP and CRP had an AUC of 0.87 (95% CI 0.78–0.96), 0.86 (95% CI 0.77–0.95) and 0.84 (95% CI 0.75–0.92), respectively (Figure 2). This evidence concerns the gene IL6 and systemic inflammatory response syndrome.