C-reactive Protein
What is analysed?
C-reactive (CRP) protein is an acute phase reactant (a protein) produced by the liver in response to inflammation in the body.
Elevated levels of CRP can occur, for example, because of tissue injury, infection, heart attack, disease, inflammatory disorders, or recent surgery.
What does the result mean?
The CRP test measures CRP levels in the bloodstream in order to indicate whether there is inflammation in the body.
The result doesn’t specify, however, the cause nor the location of the inflammation.
Why conduct the analysis?
The test may be conducted to detect inflammation, to assess the severity of the inflammation, and to monitor treatment response.
When to conduct the analysis?
The test may be conducted:
- When there is suspicion of an inflammatory disorder, such as arthritis, autoimmune disorders, or inflammatory bowel disease.
- When assessing for the possibility of infection, for example, after a surgical procedure.
What sample is required?
A blood sample is required. The blood is taken from a vein, usually in the arm.
Is any prior preparation necessary?
No prior preparation is necessary.
How is it performed?
The sample is sent to a laboratory, where it is analysed using immunoassays to detect and quantify the concentration of CRP.
What are the normal values?
| CRP levels | Interpretation |
|---|---|
| Less than 10 mg/L | Inactive inflammation |
| 10 to 30 mg/L | Slightly elevated, mild inflammation or infection |
| Greater than 30 mg/L | Elevated, acute to severe inflammation or infection |
What does having altered values mean?
- High CRP levels: Indicate the presence of inflammation, which may be due to conditions such as acute infection, autoimmune disease, or cardiovascular disease.
With chronic inflammatory conditions, elevated levels of CRP indicate either a flare-up of the condition or ineffectiveness of the treatment.