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. 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 enrolment. Plasma samples were collected 1, 2 and 7 days after enrolment to assay presepsin and procalcitonin (PCT). Outcome was assessed 28 and 90 days after enrollment. RESULTS: Early presepsin (day 1) was higher in decedents (2269 (1171--4300) pg/mL, median (Q1-Q3)) than in survivors (1184 (875--2113) pg/mL, P = 0.002) while PCT was not different (18.5 (3.4-45.2) and 10.8 (2.7-41.9) mug/L, 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) while 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 prognostic accuracy in the range of the sequential organ failure assessment (SOFA) score (area under the curve (AUC) from 0.64 to 0.75) but better than PCT (AUC 0.53 to 0.65). CONCLUSIONS: This is the first evidence in a multicenter clinical trial that presepsin measurements may provide useful prognostic information in patients with severe sepsis or septic shock. These preliminary findings suggest that presepsin may be of clinical importance for early risk stratification.