What procalcitonin brings to management of sepsis in the ICU

In inflammatory states, particularly in response to infectious stimuli, local procalcitonin (PCT) production rises, and because these tissues cannot further process PCT into calcitonin, serum levels increase. In the critical care setting, PCT should be considered a useful tool to help physicians in some specific, although frequent, situations. Serial measurements of PCT levels may indicate the effectiveness of medical decisions such as the appropriateness of antibiotic therapy, the detection of new infections, and the exclusion of a diagnosis of sepsis. PCT-guided algorithms may also help to decrease the duration of antimicrobial therapy. However, the role of PCT as a prognostic marker in critically ill patients is controversial. In a study by Karlsson and colleagues, PCT concentrations did not differ between hospital survivors and nonsurvivors, but the outcome was better in patients whose PCT concentrations decreased more than 50%. The study of PCT kinetics thus could offer an individual risk assessment in patients with severe sepsis.