Figure 1. The hyperimmune and hypoimmune phase during the progression of sepsis.

(A) The acute hyperimmune phase is characterized by systemic inflammation, immune cell and endothelial cell activation, and the release of proinflammatory mediators resulting in disrupted vascular endothelial barrier integrity, increased leukocyte trafficking, and organ damage.

(B) This hyperimmune phase often transitions into an immune compromised or hypoimmune phase characterized by decreased pathogen clearance, a shift in immune subpopulations, increased anti-inflammatory cytokines, and enhanced susceptibility to secondary infections.