Procalcitonin

Procalcitonin (PCT) is the precursor peptide, or prohormone, of the mature hormone calcitonin. Preclinical studies have demonstrated that PCT plays a pathophysiologic role in the development of severe sepsis and sepsis-related mortality, and that the PCT level can be used to help distinguish bacterial and viral infections, at least with respect to respiratory tract infections. PCT also potentially improves risk stratification and decision making with regard to antibiotic therapy in affected patients. This article addresses the use of PCT in the hospital setting regarding the differentiation of respiratory tract infections and guidance for the possible initiation of antibiotic therapy.