Blood test for suspected bacterial infections
Procalcitonin (PCT) is a protein and a prohormone to calcitonin that can be analyzed for suspected bacterial infection. Normally, it is produced in very small amounts in the thyroid gland, but in systemic bacterial infections it is released in larger amounts from other tissues in the body. This makes PCT a specific biomarker for bacterial infections and sepsis.
The difference between CRP and S-Procalcitonin?
Both CRP (C-reactive protein) and S-Procalcitonin are used to measure inflammation in the body, but they have different functions and specificity. CRP is a broader marker of inflammation that rises in both bacterial and viral infections as well as in other inflammatory conditions such as autoimmune diseases and tissue damage. Since CRP cannot distinguish between different types of infections, it is often used as a general indicator of inflammation.
Procalcitonin mainly increases in systemic bacterial infections and sepsis but usually remains low in viral infections. This makes the PCT test particularly useful when it is necessary to determine whether an infection is bacterial or viral, which can help guide antibiotic treatment and avoid unnecessary antibiotic use.
In an uncertain infection where CRP is elevated but the cause is unclear, PCT can provide more specific information about whether it is a bacterial infection and whether antibiotics may be necessary.
Why analyze S-Procalcitonin?
Analysis is recommended when serious bacterial infections or sepsis are suspected because PCT is more specific for bacterial infections than CRP.
- Help distinguish between bacterial and viral infections.
- Used to assess whether antibiotic treatment is necessary.
- Monitor the effect of antibiotics and determine whether treatment can be terminated.
- Identify severe infections such as sepsis at an early stage.
When is a PCT test appropriate and what do elevated values mean?
A PCT test is appropriate in cases of suspected serious bacterial infections, especially if symptoms are diffuse or if it is unclear whether antibiotic treatment is needed. Analysis of S-Procalcitonin may be useful in cases of fever and infections such as pneumonia, urinary tract infection or postoperative complications, to determine whether the infection is bacterial or viral.
Elevated levels of S-Procalcitonin are seen in severe bacterial infections, sepsis and more severe inflammatory conditions caused by bacteria. If a serious infection or sepsis is suspected, you should always contact your healthcare provider immediately for further investigation and treatment.
