Alone, the procalcitonin test cannot diagnose infections. However, a doctor can tell if sepsis is present, how serious it is, and if it is likely to escalate to septic shock.
Although a doctor should analyse procalcitonin test findings, they are commonly stated as follows:
- Less than 0.15 ng/ml (normal range)
- 0.15-0.49 ng/ml (minor or no significant inflammatory response in the body)
- 0.50-1.99 ng/ml (moderate risk of progression to severe systemic infection)
- More than 2.0 ng/ml (High risk or severe sepsis)
High procalcitonin level, it’s likely you have a severe bacterial infection such as sepsis or meningitis. The higher the level, the more serious your infection. If you are being treated for an infection, decreased or low procalcitonin levels may indicate that your therapy is effective.
The test can also tell you whether you have a bacterial or viral infection. A viral infection is more likely if the symptoms are severe, yet procalcitonin level is very low. This will help your doctor to plan your treatment accordingly while avoiding the unnecessary usage of antibiotics.
When a person is being treated for sepsis or bacterial infection, declining procalcitonin levels over time indicate a response to therapy. Procalcitonin levels that are stable or rising may suggest that medication should be continued.
Thing to Note: The reference ranges depend on many factors, like patient age, sex, and test method, and ranges can be different in different laboratories.