Procalcitonin and C-reactive Protein in Septicaemia: Correlation With Bacterial Profile and Antimicrobial Resistance in ICU Setting.

Septicemia remains a major cause of morbidity and mortality among critically ill patients admitted to intensive care units (ICUs), particularly in regions facing a growing burden of antimicrobial resistance. Early diagnosis and prompt initiation of appropriate antimicrobial therapy are essential for improving patient outcomes; however, conventional blood culture methods often require prolonged turnaround times, limiting their utility in urgent clinical decision-making. This narrative review aims to summarize current evidence regarding the epidemiology, microbiological characteristics, antimicrobial resistance patterns, and clinical utility of inflammatory biomarkers in ICU-associated septicemia, with particular emphasis on C-reactive protein (CRP) and procalcitonin (PCT). Relevant peer-reviewed literature was identified through a review of published studies, reviews, and clinical guidelines addressing septicemia, biomarker performance, antimicrobial resistance, and antimicrobial stewardship in critical care settings. Available evidence suggests that gram-negative pathogens remain predominant causes of ICU septicemia and are frequently associated with elevated PCT concentrations due to endotoxin-mediated inflammatory responses. Compared with CRP, PCT generally demonstrates earlier elevation following bacterial infection, greater specificity for bacterial sepsis, and a closer association with disease severity. However, both biomarkers have limitations, particularly in predicting mortality and clinical outcomes. Current evidence supports the use of biomarkers as adjunctive tools rather than standalone diagnostic tests. PCT-guided antimicrobial strategies may contribute to improved antimicrobial stewardship and reduced unnecessary antibiotic exposure in selected patient populations. Overall, optimal management of septicemia requires integration of clinical assessment, microbiological investigations, and biomarker data to support timely and informed therapeutic decisions.