In contrast, higher day 1 levels of TNF-α, IL-6, IL-8, and CRP (p = 0.013, p < 0.001, p = 0.001, and p = 0.017, respectively), but not IL-1β (p = 0.057), were observed in patients with septic shock compared with those with severe sepsis (S1 Table). Here, CRP is linked to septic shock.