A C-reactive protein test (CRP) is a blood test that detects general inflammation in the body.
CRP, which is produced by the liver, plays an important role in the immune system.
Levels increase when there’sinflammationwhich can be due to an infection, disease, or injury.
Verywell / Emily Roberts
CRP tests provide an early clue that something is wrong in the body.
Verywell / Emily Roberts
What Is C-Reactive Protein?
C-reactive protein is a protein produced by the liver that is normally found in the bloodstream at low levels.
Why Is the CRP Test Done?
The CRP test is used to determine if your symptoms are related to an inflammatory condition.
Based on how high the CRP levels are, the lab can narrow the likely suspects.
The higher the CRP levels, the greater the amount of inflammation in the body.
With heart disease, CRP levels tend to be modestly elevated and will gradually increase as the disease progresses.
In some cases, a CRP test can be the deciding factor even if levels are only mildly elevated.
What Is a High C-Reactive Protein Level?
A CRP level over 50 mg/L is considered alarming.
Based on your CRP levels, a doctor can begin to narrow down the possible causes of an illness.
It usually takes less than five minutes.
A CRP test doesn’t require fasting beforehand.
Speak with your healthcare provider or the lab to double-check.
If they don’t or get worse, call your healthcare provider.
The follow-up of a CRP test can vary based on your diagnosis.
The treatment or next steps will depend on that diagnosis.
If you have health insurance, your plan should cover the cost at least in part.
The CRP test only requires a simple blood draw.
There are many, including infection, pancreatitis, an autoimmune disorder, or cancer.
The high-sensitivity CRP is a variation of this test used to predict the risk of heart attack or stroke.
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MedlinePlus.Erythrocyte sedimentation rate (ESR).
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