The accuracy of PCT was higher than that of othermarkers, including CRP; however, it was less accurate than the CURB-65 (AUC0.88) and PSI (AUC 0.89) scores.(36) Furthermore, in a study that evaluated the ability of PCTand other markers to predict treatment failure (occurrence of septic shock, needfor mechanical ventilation, or death within 72 hours) and included 453 patientswith a diagnosis of CAP, higher levels of PCT (averaging 3.36ng/mL) measured atthe baseline the were independent predictors of early treatment failure, withlow levels presenting a high NPV for this outcome (0.95).(37). The gene discussed is CALCA; the disease is septic shock.