# Is calprotectin a reliable marker in surgical ICU settings? A clinical evaluation of its role in sepsis and mortality prediction

## TL;DR

This study finds that calprotectin is not a reliable marker for sepsis or mortality prediction in surgical ICU patients.

## Contribution

The study evaluates calprotectin's diagnostic and prognostic value in surgical ICU settings, revealing its limitations and potential complementary role.

## Key findings

- Calprotectin showed poor prognostic accuracy (AUC = 0.472) for mortality prediction.
- Calprotectin correlated with PCT in sepsis but not in postoperative subgroups.
- Mortality was associated with CRP and severity scores, not calprotectin levels.

## Abstract

Calprotectin, a neutrophil-derived protein, has emerged as a potential biomarker for inflammation and infection. This study evaluated the utility of serum calprotectin levels in diagnosing sepsis and predicting mortality in surgical intensive care unit (ICU) patients.

This prospective observational study included 124 patients admitted to the surgical ICU at Uşak Training and Research Hospital between 2022 and 2024. Data on demographics, serum calprotectin, CRP, PCT, lactate levels, and clinical scores (SOFA, APACHE II) were collected. ROC analysis was used for predictive accuracy; Spearman and Pearson correlation coefficients assessed associations.

No significant associations were found between serum calprotectin and SOFA/APACHE II scores, CRP, or lactate. However, calprotectin correlated positively with PCT in sepsis (r = 0.428, p = 0.002) negatively in postoperative subgroups (r = −0.48, p < 0.001). Calprotectin showed poor prognostic accuracy (AUC = 0.472). Mortality was significantly associated with high CRP and severity scores, but not with calprotectin levels.

Calprotectin alone lacks sufficient diagnostic or prognostic power for sepsis in surgical ICU patients. It may serve as a complementary marker alongside PCT in specific subgroups.