Presepsin (soluble CD14 subtype) and procalcitonin levels for mortality prediction in sepsis: data from the Albumin Italian Outcome Sepsis trial

Introduction: Sepsis, a leading cause of death in critically ill patients, is the result of complex interactions between the infecting microorganisms and the host responses that influence clinical outcomes. We evaluated the prognostic value of presepsin (sCD14-ST), a novel biomarker of bacterial infection, and compared it with procalcitonin (PCT). Methods: This is a retrospective, case-control study of a multicenter, randomized clinical trial enrolling patients with severe sepsis or septic shock in ICUs in Italy. We selected 50 survivors and 50 non-survivors at ICU discharge, matched for age, sex and time from sepsis diagnosis to enrollment. Plasma samples were collected 1, 2 and 7 days after enrollment to assay presepsin and PCT. Outcome was assessed 28 and 90 days after enrollment. Results: Early presepsin (day 1) was higher in decedents (2,269 pg/ml, median (Q1 to Q3), 1,171 to 4,300 pg/ml) than in survivors (1,184 pg/ml (median, 875 to 2,113); P = 0.002), whereas PCT was not different (18.5 mu g/L (median 3.4 to 45.2) and 10.8 mu g/L (2.7 to 41.9); P = 0.31). The evolution of presepsin levels over time was significantly different in survivors compared to decedents (P for time-survival interaction = 0.03), whereas PCT decreased similarly in the two groups (P = 0.13). Presepsin was the only variable independently associated with ICU and 28-day mortality in Cox models adjusted for clinical characteristics. It showed better prognostic accuracy than PCT in the range of Sequential Organ Failure Assessment score (area under the curve (AUC) from 0.64 to 0.75 vs. AUC 0.53 to 0.65). Conclusions: In this multicenter clinical trial, we provide the first evidence that presepsin measurements may have useful prognostic information for patients with severe sepsis or septic shock. These preliminary findings suggest that presepsin may be of clinical importance for early risk stratification.