Procalcitonin is a biomarker for systemic bacterial infections

Procalcitonin (PCT) is a biomarker used to identify systemic bacterial infections, particularly sepsis. It plays a crucial role in differentiating between viral and bacterial sepsis, as it remains normal or only slightly elevated in viral infections, unlike in bacterial infections.

While PCT levels can sometimes rise in non-infectious inflammatory conditions, it is especially valuable in guiding antibiotic therapy, particularly in the era of multi-drug resistance.

Key Clinical Use:
If PCT levels decrease by 80% from their peak, antibiotics can be safely stopped, regardless of the number of days they have been used. This approach helps in:

• Avoiding new infections caused by multi-drug-resistant organisms.
• Reducing the risk of Clostridioides difficile (C. difficile) infections.

Evidence from Clinical Trials:
The use of PCT has been proven to:

• Shorten the duration of antibiotic therapy.
• Reduce 28-day mortality rates.
• Improve outcomes even after 6 months, as demonstrated in one of the largest trials, PROGRESS.