Utilized to reduce use of antibiotics in infections.
A precursor to calcitonin.
Does not directly influence calcitonin or calcium levels.
A measure of systemic inflammation due to bacteria.
Acts in a similar manner to inflammatory cytokines.
Levels rise and fall quickly.
In healthy individuals serum levels are undetectable.
With bacterial infections messenger RNA for calcitonin is upregulated.
Procalcitonin production is attenuated by cytokines linked to viral infections.
Procalcitonin levels rise within 1 to 2 hours of sepsis.
The biomarker procalcitonin may improve clinical judgment to diagnosis and course of a bacterial community acquired pneumonia, as synthesis a procalcitonin is triggered by specific cytokines in response to bacteria.
Has a high negative predictive value, meaning that, if it is negative, there is a very good chance that there is not a systemic inflammatory reaction due to bacteria.
Levels are not elevated if there is a bacterial infection that is not causing a systemic inflammatory response.
Trending levels trend in systemic bacterial infections is more valuable than the quantitative result.
As the level of PCT drops, the prognosis improves.
A decline of 30% in 24 hours suggests a significant improvement in inflammation, and if the level declines more than 80% or if levels are between 0.25 and 0.5 ng/ml, antibiotics can be stopped, reducing the duration of antibiotic therapy.
Using an algorithm with procalcitonin in patients with lower respiratory tract infections compared with standard guidelines was associated with lower rates of antibiotic exposure and antibiotic adverse effects, but similar rates of adverse outcomes (The ProHosp Randomized Controlled Trial).
Procalcitonin guided antibiotic management reduces initial antibiotic prescription rates by 40-50% in patients with lower respiratory tract infections presenting to emergency departments, and by 70-80% in ambulatory patients presenting to their physician, and reduced antibiotic exposure in community acquired pneumonia by 40-50%.
Use discourages antibiotic initiation in bronchitis and acute exacerbation of COPD and shortens antibiotic courses in a community acquired pneumonia without increasing rates of adverse outcomes.
Higher circulating levels and protracted normalization of such levels correlate with a more severe systemic infection, mirroring a slower bacterial clearance and stronger virulence of the microorganism.
Can provide discrimination for the diagnosis and exclusion of pneumonia when there is uncertainty between diagnosis of heart failure and pneumonia.
Elevated level is a predictor of 1 year mortality in patients with pneumonia.
Levels or typically low in viral community acquired pneumonia.
False positive tests can occur in hemorrhagic, shock or kidney injury.
Some bacteria, such as mycoplasma can cause pneumonia with normal procalcitonin levels.