Procalcitonin Thresholds

Current 2021 sepsis guidance weakly recommends against using procalcitonin to initiate antibiotics because evidence certainty is very low. A fixed PCT value can rise after non-infectious insults, including trauma and sterile inflammation. Surgery and sterile inflammation can increase procalcitonin without bacterial infection. A fixed PCT threshold is limited because PCT reflects host response, which varies between patients. Treating isolated PCT values such as 0.5 or 1.0 ng/mL as antibiotic triggers can cause overtreatment. Low PCT thresholds in prior surgical populations may have made antibiotic overuse an expected trial-design consequence.