Fig. 2
From: Procalcitonin-guided diagnosis and antibiotic stewardship revisited

Procalcitonin (PCT) algorithm in patients with respiratory tract infections in the emergency department. The clinical algorithm for antibiotic stewardship in patients with respiratory tract infections in the emergency department encourages (>0.5 ng/ml or >0.25 ng/ml) or discourages (<0.1 ng/ml or <0.25 ng/ml) initiation or continuation of antibiotic therapy more or less based on specific PCT cut-off ranges. Abbreviations: AB antibiotic, LRTI lower respiratory tract infection, ICU intensive care unit, PSI pneumonia severity score