Procalcitonin as a Diagnostic Biomarker of Sepsis: A Prospective Study in a Tertiary Care Centre

Introduction: Sepsis is remains a prominent source of morbidity and mortality, despite advances in diagnostic methods. It's still hard to differentiate between sepsis and non-infectious disease conditions. The procalcitonin (PCT) test is beneficial for diagnosing sepsis, however the cut-off levels vary depending on the clinical context. The goal of this study was to determine the appropriate cut-off values for PCT with high sensitivity and specificity by correlating serum PCT levels with cultures. Methodology: This prospective study comprised 305 patients from various hospital wards; the patients were classified into group I: controls (n = 46), group II: Culture-negative sepsis (n = 76) and group III: Culture-positive sepsis (n = 196). Mean p value <0.05 was considered significant. Results: In comparison to group I, PCT levels were significantly higher in groups II and III. In group II, the best cut-off point for PCT was 1.3 ng/ml with 87.30% sensitivity and 78.26% specificity (area under curve 0.86). In group III, the best cut-off value of 2.20 ng/ml with 98.47% sensitivity and 89.13% specificity was found (AUC 0.96). Conclusion: Procalcitonin is a promising biomarker for bacterial sepsis diagnosis since it can differentiate culture-negative and culture-positive sepsis from non-infectious diseases.