The role of procalcitonin outside of the Intensive Care Unit (ICU): a multidisciplinary approach.

Biochemical markers are commonly used in medicine to guide diagnostic investigation or therapy duration and/or monitor treatment efficacy. Due to the emergence and spread of antimicrobial resistance, markers able to prompt a more rational use of antimicrobial therapy are regarded with the greatest attention. Procalcitonin (PCT) certainly stands out among others, yet its role must be better established especially outside of the critical care area. Data about PCT utilization in non-critical patients, optimal negativity cut-offs as well as a protocol for measurement timing are all lacking. To address these issues, a focus group was set up to propose and endorse shared statements regarding the most beneficial use of PCT in real life as infection marker for non-critical patients, based on the authors' experience and a review of recent literature. A group of nine experts in the fields of Infectious Diseases, Internal Medicine, Microbiology, Clinical Chemistry, Surgery and Medical Economics participated in the discussion of nine pre-specified statements. The potential role for PCT in differentiating infectious and non-infectious clinical syndromes and guiding antimicrobial therapy discontinuation was acknowledged. Moreover, a shared measurement protocol and desirable cut-offs for the non-critical area were proposed. Finally, observations were made about a reasonable selection of the patient population to be tested.