Comparison between presepsin, procalcitonin, and CRP as biomarkers to diagnose sepsis in critically ill patients.

Background and aims: Mortality associated with sepsis continues to remain high. Early diagnosis and aggressive management may improve outcomes. Biomarkers may help in early diagnosis, but the search for an ideal biomarker continues. Presepsin has been introduced as a new biomarker, however, it still needs validation before its use becomes routine. In this study, we aimed to compare the efficacy of various biomarkers in patients with suspected sepsis.

Material and methods: A retrospective analysis of 100 patients with suspected infection, admitted in the medical intensive care unit (ICU) was conducted. Diagnosis of sepsis was made on the basis of the current surviving sepsis guidelines criteria.

Results: Out of 100 patients, 70 were diagnosed to have sepsis, and overall ICU mortality was 22%. Overall, C-reactive protein (CRP) was positive in 98, procalcitonin in 75, and presepsin in 64 patients. For diagnosis of sepsis the sensitivity, specificity, and AUC, respectively, for CRP was 98.6%, 3.3%, and 0.725. For procalcitonin (>0.5 ng/ml) it was 87.1%, 53.3%, and 0.776, and for procalcitonin (>1 ng/ml) 70%, 70%, and 0.816, respectively. For presepsin sensitivity, specificity, and AUC, respectively, for diagnosis of sepsis was 77.1%, 66.7%, and 0.734. For ICU mortality, sensitivity and specificity for CRP was 95.5% and 1.3%, for procalcitonin (>0.5) 72.7% and 24.4.%, for procalcitonin (>1) 59.1% and 42.3%, and for presepsin 61.5% and 27.3%, respectively.

Conclusion: Inflammatory markers may be raised in a large proportion of ICU patients, even in those without sepsis. Procalcitnonin and presepsin had similar efficacy in diagnosing sepsis. However, none of the three biomarkers studied were accurate in predicting ICU mortality.