An important negative study of an inflammatory biomarker that’s been getting a fair amount of push.
It is absolutely true that procalcitonin levels may be elevated in an inflammatory states such as sepsis. This group tried to make a clinically relevant protocol for procalcitonin trends by saying, if the procalcitonin level is not decreasing with current therapy, then antibiotic coverage should be expanded and aggressive testing should be undertaken to evaluate for missed source control.
Unfortunately, in the treatment arm where procalcitonin was used in clinical decision making, there was extensively greater broad-spectrum and multiple-antibiotic utilization without any demonstrated mortality benefit. In addition, LOS and ventilator-depended days were longer in the procalcitonin arm.
There were very minor differences between the two groups, probably favoring the control, but not nearly enough to suggest that procalcitonin has any value in assessing failure of current therapy.
Love the blog and find myself reading through much of your comments (unfortunately I am playing catch up).
We still use procalcitonin at my shop (including initial level sent for PNA in patients admitted from the ED). We do this in order to try and reduce abx exposure, rather use it to escalate therapy as was done in this paper, as Procalcitonin levels are sent daily. I don't think its perfect but an arbitrary guideline for number of days of abx exposure as delineated by CHEST, or GOLD. I'm still holding out for something better.
The trial we looked at was Scheutz et alThe ProHOSP Randomized Controlled Trial JAMA 2009.