CRP - C Reactive Protein

🏾 Contents:

Le CRP est mesurée à l'aide d'un petit échantillon de sang prélevé dans une veine de votre bras.

🏾 What is the normal CRP value?

The measured CRP is expressed in milligrams per liter (mg/L) or mg/dL.

Although “normal” CRP levels vary from lab to lab, it is generally accepted that a value below 10 mg/L (1.0 mg/dL) is normal.

Test results may vary depending on your age, gender, medical history, test method used and other factors (CRP levels may be higher in women, patients on hormone therapy replacement therapy or a high body mass index).

Note : For some references the normal value is less than 6 mg/L (0.6 mg/dL )

🏾 Preparation for the CRP test

In general, there are no special preparations to make before the test, it is a routine blood test that can be done at any time and does not require fasting, unless your blood sample will be used for further testing, you may need to avoid eating or drinking for some time before the test.

Note : Take your list of medications with you, some medications (Aspirin, ibuprofen or estrogen), Tobacco or alcohol can interfere with CRP measurement

🏾 CRP Results: Interpretation

High CRP

◾ Given the highly variable causality of elevated CRP, marginal elevations in CRP can be difficult to interpret. An elevation in CRP above 10 mg/L may mean that your body is having an inflammatory reaction to something but will not identify its location or cause (further testing will be needed to determine what is causing the inflammation.).

Example : Osteomyelitis, rheumatoid arthritis, irritable bowel syndrome, tuberculosis, lupus, certain types of cancer, especially lymphoma inflammation…

◾ Very high levels of CRP, above 50 mg/L, are very often associated with bacterial infections.

◾ In the case of a chronic inflammatory disease: high levels of CRP suggest a flare-up if you have a chronic inflammatory disease or if the treatment has not been effective.


◾ Just indicates an absence of inflammatory syndrome.

🏾 Covid-19 and C-reactive protein

A significant increase in CRP was found with levels averaging 20 to 50 mg/L in patients with COVID-19.

Patients with severe disease course had much higher CRP levels than mild or non-severe patients.

🏾 What other tests could I have with this test?

🏾 C-reactive protein and Pregnancy

Pregnancy can elevate CRP levels, especially during the later stages.

🏾 Difference Between CRP and Sedimentation Rate (ESR)

Compared to erythrocyte sedimentation rate, which is an indirect test of inflammation, CRP levels rise and fall rapidly with onset and suppression of inflammatory stimulus, respectively.

🏿 Frequently Asked Questions

Q: What does a high CRP level mean?
A: An elevated CRP test result is a sign of acute inflammation. This may be due to a serious infection, injury, or chronic illness. Your doctor will recommend further tests to determine the cause.

Q: My doctor prescribed a CRP test to detect an infection!!
A: Your doctor may order a CRP test to check for an infection if you have symptoms of inflammation such as fever, chills, flushing or flushing, nausea, vomiting, rapid breathing and/or rapid heart rate.

Q: Does CRP increase in viral infections?
A: CRP levels can also increase when you have a viral infection. But they do not rise as high as during a bacterial infection. Your doctor will recommend further tests to determine the cause.


  1. Sara M - C Reactive Protein
  2. University of Rochester Medical Center Rochester - C-Reactive Protein
  3. Jennifer Huizen - What does it mean if you have a high C-reactive protein?
  4. Medical Encyclopedia. C-reactive protein. Updated January 31, 2021 - C Reactive Protein
  5. labocorp - C-Reactive Protein (CRP)
  6. The Johns Hopkins University - Assessing Cardiovascular Risk with C-Reactive Protein
  8. Nurshad Ali - Elevated level of C‐reactive protein may be an early marker to predict risk for severity of COVID‐19