Comparative Analysis of Procalcitonin and C-reactive Protein as Biomarkers in Sepsis Diagnosis for Patient Admitted in ICU: Correlation with Blood Culture Positivity

Background: Sepsis is a life-threatening condition that requires early and accurate diagnosis to improve clinical outcomes.Blood culture remains the gold standard for diagnosing bacterial sepsis.However, its limitations, including low sensitivity and long processing time, have prompted the use of biomarkers such as procalcitonin (PCT) and C-reactive protein (CRP).This study compares the diagnostic performance of PCT and CRP in detecting sepsis and their correlation with blood culture positivity.Materials and methods: A prospective observational study was conducted at Mahaveer Institute of Medical Sciences, Bhopal, from January to November 2024.A total of 250 patients suspected of sepsis were enrolled.Serum levels of PCT and CRP were measured and compared with the results of blood cultures.Diagnostic accuracy was assessed using receiver operating characteristic (ROC) curve analysis.Sensitivity, specificity, and correlation coefficients were calculated to determine the clinical utility of both biomarkers.Results: Procalcitonin demonstrated higher sensitivity (88.5%) and specificity (82.1%) compared to CRP (72.3 and 65.8%, respectively).Procalcitonin levels were significantly elevated in septic patients (6.5 2.1 ng/mL) compared to nonseptic patients (0.8 0.3 ng/mL, p < 0.001).Similarly, PCT showed a stronger correlation with blood culture positivity (r = 0.78) compared to CRP (r = 0.55).Receiver operating characteristic analysis revealed a significantly higher area under the curve (AUC) for PCT (0.91) than for CRP (0.75), indicating superior diagnostic accuracy. Conclusion:Procalcitonin is a more reliable biomarker for sepsis diagnosis than CRP, demonstrating superior sensitivity, specificity, and correlation with blood culture positivity.Its early detection capability can aid in prompt clinical decision-making, optimizing antibiotic use, and improving patient outcomes.Further research is recommended to validate these findings in larger multicenter studies.