Procalcitonin-guided antibiotic therapy: an expert consensus.

PCT use is appropriate in algorithms for antibiotic de-escalation and discontinuation. In this case, reproducible, high sensitive assays should be used. However, initiation or escalation of antibiotic therapy in specific scenarios, including acute respiratory infections, should not be based solely on PCT serum levels. Clinical and radiological findings, evaluation of severity of illness and of patient's characteristics should be taken into proper account in order to correctly interpret PCT results.