Utility of Procalcitonin as a Diagnostic Tool for Sepsis in Intensive Care Units


C-reactive Protein
SOFA Score
Intensive Care

How to Cite

Bennouar, S. ., Cherif , A. B., & Abdi, S. (2022). Utility of Procalcitonin as a Diagnostic Tool for Sepsis in Intensive Care Units. Current Medicine. https://doi.org/10.55085/cm.2022.607


Introduction/Objective: Sepsis is one of the leading causes of mortality in the intensive care unit (ICU). Its diagnosis is often complex and represents a real clinical challenge. The objective of this study was to evaluate the usefulness of procalcitonin (PCT) as a diagnostic marker of sepsis. 
Methods: This prospective cohort study included 65 patients hospitalized in the ICU. Demographic and clinical data were collected according to a specific information sheet. All patients underwent an inflammatory assessment including PCT, hypersensitive C - reactive protein (hsCRP), and complete blood count. The Sequential Organ Failure Assessment (SOFA) score was calculated. Patients were classified into septic (SOFA ≥ 2 points) and non-septic (SOFA < 2 points). The Receiver Operating Characteristic (ROC) curve was used to evaluate the diagnostic performance of inflammatory parameters.
Results: Of 65 included patients, 46 had developed sepsis. Among the investigated inflammatory markers, PCT has the best discriminative capacity; its area under the curve (AUC), of 0.78, was the highest, followed by the neutrophils to lymphocytes ratio (NLR) and hsCRP with a lower but statically significant AUC. The optimal PCT threshold for sepsis diagnosis was 4.5ng/ml with a specificity of 83% and a sensitivity of 60%. A positive correlation between the PCT levels and the SOFA score was also found (p=0.002).
Conclusion: This study provides additional evidence of the performance of PCT in the diagnosis of septic states in patients admitted to ICU. The newly established cut-off value provides the best balance between specificity and sensitivity. Its superiority over conventional inflammatory markers has been demonstrated.



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