CRP is a protein that is produced by the liver in response to inflammation in the body. This biomarker plays a crucial role in the immune system by detecting and responding to harmful invaders like bacteria or viruses. It also contributes to the healing of damaged tissue.

Doctors use CRP levels to diagnose and monitor a variety of inflammatory conditions, like infections or autoimmune diseases. CRP is also used to assess the risks of cardiovascular disease, especially when combined with other risk factors such as high cholesterol.

CRP is not routinely included in routine health checkups, but it may be prescribed in the presence of inflammatory symptoms or other specific conditions.

Indications for a CRP Test:

• Unexplained fever : A prolonged or high fever may signal an underlying infection or inflammation.
• Suspected bacterial infection : CRP may help confirm the diagnosis.
• Chronic inflammatory symptoms : Joint pain, swelling, or stiffness, often linked to conditions such as rheumatoid arthritis.
• Heart symptoms : Chest pain, rapid heart rate, or shortness of breath that may indicate a cardiovascular problem.
• Post-surgery or injury : Monitor recovery and detect complications, such as infection.
• Suspected autoimmune diseases : Conditions such as lupus or inflammatory bowel disease.

CRP is measured by a simple blood test. The most common test is the high-sensitivity CRP test (hs-CRP), which can detect even low levels of inflammation.

Test process:

1. Blood sample : A health professional takes a blood sample from a vein, usually from the arm.
2. Laboratory analysis : CRP levels are measured using techniques such as latex agglutination, which can detect minor variations.

Preparations:

• No special preparation is usually required. You can eat and drink normally before the test.
• Avoid strenuous physical activity prior to the test, as it may temporarily increase CRP levels.

Normal levels vary slightly depending on age and specific conditions:

• Adults : Less than 5 mg/L
• Pregnant women :
  • Up to 12 weeks: 0-5 mg/L
  • 12-27 weeks: 0.4-20.3 mg/L
  • 27-42 weeks: 0.4-8.1 mg/L

note : Reference units and ranges may vary between laboratories.

High levels of CRP signal inflammation in the body. However, they do not make it possible to diagnose a specific disease. Some common causes include:

Causes of High Levels:

• Infections : Pneumonia, sepsis, or other bacterial infections often lead to a sharp increase.
• Chronic inflammatory diseases : Rheumatoid arthritis, lupus, or other autoimmune conditions.
• Traumas or injuries : A temporary increase is common during healing.
• Heart attack : A sudden rise may occur after a heart attack.
• Cancers : Certain types of cancer associated with chronic inflammation.
• Serious burns : Extensive tissue damage leads to increased levels.

Recommendations for Managing High Levels:

• Reducing inflammation : Adopt an anti-inflammatory diet rich in omega-3, fruits and vegetables.
• Practicing regular physical activity : Moderate exercise may reduce inflammation.
• Managing stress : Use techniques like meditation or yoga.
• Quit smoking : Smoking increases CRP levels.
• Maintaining a healthy weight : Obesity is linked to high levels of inflammation.

If your CRP levels are high, choosing a specialist depends on the underlying cause:

• General practitioner : For initial assessment and possible guidance.
• Cardiologist : In case of a link with cardiovascular disease.
• Rheumatologist : For inflammatory conditions such as lupus or rheumatoid arthritis.
• Infectiologist : If a serious infection is suspected.

Prompt and appropriate management is essential to manage the causes of high CRP and to prevent complications.