Interpretation of procalcitonin levels in respiratory tract infections

Level (ng/mL)	Likelihood of bacterial infection*
<0.10	Very unlikely
0.10 to 0.25	Unlikely
0.25 to 0.50	Likely
>0.50	Very likely

* This interpretation assumes a clinically compatible syndrome and the absence of other causes of procalcitonin elevation.

Graphic 117054 Version 1.0