Presepsin versus other biomarkers to predict sepsis and septic shock in patients with infection defined by Sepsis-3 criteria: the PREDI study of diagnostic accuracy

Objectives. An accurate diagnosis of sepsis in the emergency department must be made before appropriate treatment can be started. Many biomarkers that are potentially useful have been studied. The main aim of this study was to compare the diagnostic accuracy of blood levels of presepsin, lactate, C-reactive protein (CRP), and procalcitonin (PCT) for predicting sepsis as defined by the Sepsis-3 criteria. The secondary aim was to evaluate the diagnostic accuracy of these biomarkers for predicting bacteremia whether or not sepsis or septic shock was present. Methods. Single-center, prospective, observational cohort study in the emergency department of a university hospital. Consecutive patients suspected of having infection were enrolled prospectively if they had at least 2 criteria for systemic inflammatory response syndrome. We measured presepsin, PCT, CRP, and lactate in blood extracted on admission. Results. Blood samples from 359 patients were analyzed; 228 (63.5%) met the criteria for sepsis and 20 (5.6%) met the criteria for septic shock. PCT and presepsin levels were the best predictors of sepsis and septic shock with areas under the receiver operating characteristic curve (AUC) of 0.711 (95% CI, 0.660-0.758) and 0.709 (95% CI, 0.658-0.756), respectively (P<.001, both comparisons). The AUCs for CRP and lactate concentrations were, respectively, 0.63 (95% CI, 0.58-0.69) and 0.61 (95% CI, 0.56-0.66) (P<.05, both comparisons). On applying the diagnostic cut points of 0.25 ng/mL for PCT and 500 pg/mL for presepsin, the odds ratios were 2.51 (95% CI, 1.53-4.12) for PCT and 3.19 (95% CI, 1.91-5.31) for presepsin. The diagnostic accuracy of the combination of presepsin and PCT results (AUC, 0.71; 95% CI 0.66-0.76; P<.001) was no better than the accuracy of PCT alone. The most accurate predictor of bacteremia was PCT (AUC, 0.835; 95% CI, 0.79-0.87; P<.001). Conclusion. Presepsin and PCT seem to be the best predictors of a diagnosis of sepsis or septic shock in emergency department patients.