IL6 and Sepsis: Key sepsis biomarkers such as PCT, CRP, and IL-6 are measured at the time of patient evaluation, with a PCT > 2 ng/mL that often indicates a serious bacterial infection requiring aggressive antibiotic therapy and an elevated PCT < 0.5 ng/mL, but CRP and IL-6 indicate a complication of nonisolated bacterial inflammation and a shift to another clade [61].