Calprotectin as a Prognostic Marker for Sepsis Independent of Renal Dysfunction

Background: The role of calprotectin in sepsis pathophysiology is becoming increasingly recognized; however, optimal biomarkers for sepsis prognosis are lacking. We compared the prognostic accuracy of calprotectin with that of established biomarkers. Methods: In this single-center prospective cohort study, patients who met the Sepsis-3 criteria were recruited between December 2022 and January 2024. Blood samples were collected at sepsis recognition (day 0) in the emergency department and on days 3 and 7 during the intensive care unit admission. Results: <0.001). After estimated glomerular filtration rate (eGFR) adjustment, the predictive performance of calprotectin was preserved, whereas presepsin and procalcitonin showed significant renal function dependency. Calprotectin did not significantly correlate with eGFR and showed good prognostic performance regardless of renal dysfunction status. Incremental value analyses revealed that serial calprotectin measurements provided no significant improvement over baseline assessment. In pneumonia-induced sepsis, calprotectin consistently showed the highest AUC, regardless of renal adjustment. Conclusions: Calprotectin demonstrated reliable prognostic performance for hospital mortality in community-onset sepsis independently of renal dysfunction, warranting validation in larger cohorts. A single measurement at initial presentation could provide clinically useful early prognostic information.