Procalcitonin (PCT) is a precursor of the hormone calcitonin, which is involved with calcium homeostasis, and is produced by the C-cells of the thyroid gland.
In healthy people, procalcitonin (PCT) concentrations are low, but in those with bacterial infection it occurs at high concentrations in the blood as early as 3 hours after infection. In people with viral infections, procalcitonin (PCT) levels rise only marginally, if at all.
A PCT-guided strategy applied in primary care in unselected patients presenting with symptoms of acute respiratory infection reduces antibiotic use by 41.6 percent without compromising patient outcome.
The FDA Approved an Automated Procalcitonin (PCT) Test in 2008.
Simple test could cut excessive antibiotic use. Reuters, 2010.