CRP: Key Facts, Functions and Health Risks

What Is C-reactive Protein (CRP)?

CRP, or C-reactive protein, is a protein produced by the liver in response to inflammation in the body. This biomarker is crucial in your immune system’s response to injury or infection. CRP helps your body detect and react to harmful invaders, such as bacteria or viruses and assists in healing damaged tissues.

Healthcare providers use CRP levels to diagnose and monitor a variety of conditions. Since elevated CRP is often a sign of inflammation, it can be used to detect infections, autoimmune diseases, and other inflammatory conditions. Monitoring CRP levels can also help doctors track how well treatments are working, particularly in conditions like rheumatoid arthritis or heart disease.

In addition to its role in inflammation, CRP is sometimes used as a marker to assess the risk of cardiovascular disease, especially when combined with other risk factors such as high cholesterol.

When Is CRP Testing Recommended?

CRP testing is not typically part of routine medical check-ups, but doctors may recommend it when there are signs of inflammation or other related conditions. Here are some common reasons a doctor might prescribe a CRP test:

• Unexplained fever: Prolonged or high fever can indicate an underlying infection or inflammation.
• Suspected bacterial infection: Doctors may use CRP levels to help diagnose bacterial infections.
• Chronic inflammation symptoms: If a patient experiences continuous joint pain, swelling, or stiffness, this test can help identify underlying inflammatory diseases like rheumatoid arthritis.
• Heart disease symptoms: If a person experiences chest pain, rapid heart rate, or shortness of breath, a CRP test may be used to assess heart health.
• Post-surgery or injury: To monitor recovery and detect possible complications, such as infection.
• Autoimmune disease: Conditions like lupus or inflammatory bowel disease (IBD) can cause elevated CRP levels, so the test may help in diagnosing or monitoring these diseases.

How Is CRP Testing Conducted?

CRP is measured through a simple blood test. The most common type of test used to measure CRP levels is called a high-sensitivity CRP test (hs-CRP), which can detect even low levels of inflammation in the body. Here’s how the testing process works:

1. Blood sample collection: A healthcare provider will draw a small sample of blood, usually from a vein in your arm.
2. Laboratory analysis: The blood sample is sent to a lab, where the CRP level is measured using methods such as latex agglutination. This test is sensitive and can detect even minor changes in CRP levels.

Generally, no special preparations are required for CRP testing. You can eat and drink as normal before the test. However, some doctors may ask you to avoid exercise or strenuous physical activity before the test, as this can temporarily increase CRP levels.

What Are the Normal CRP Levels?

In general, the following ranges are considered standard:

• 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: The units of measurement and the normal ranges can differ depending on the laboratory and the specific methods used

What Do High CRP Levels Mean?

Elevated CRP levels indicate that there is some form of inflammation in the body. However, high levels do not point to a specific condition and can be linked to a range of health issues. Here are some common causes of elevated CRP levels:

• Infections: Bacterial infections, such as pneumonia or sepsis, often cause a rapid rise in CRP levels.
• Chronic inflammatory diseases: Conditions like rheumatoid arthritis and lupus lead to ongoing inflammation, resulting in consistently high CRP.
• Trauma or injury: Physical injuries or surgeries can cause temporary increases in CRP as the body heals.
• Heart attack: A sudden rise in CRP levels can occur after a heart attack, indicating damage to heart tissues.
• Cancer: Some cancers, particularly those that affect the immune system or cause chronic inflammation, may be associated with higher CRP levels.
• Severe burns: CRP levels may spike in response to the extensive tissue damage caused by burns.

Recommendations

If you have high CRP levels, working closely with your healthcare provider is important to identify and manage the underlying cause. Here are some general recommendations for managing elevated CRP levels:

• Work on reducing inflammation: Focus on an anti-inflammatory diet, which includes foods rich in omega-3 fatty acids, fruits, and vegetables.
• Exercise regularly: Moderate physical activity has been shown to help reduce inflammation in the body.
• Manage stress: Chronic stress can increase inflammation, so techniques like mindfulness, meditation, or yoga may help lower your CRP levels.
• Quit smoking: Smoking is known to elevate CRP levels, so quitting can help reduce inflammation.
• Control weight: Obesity is linked to higher levels of inflammation. Losing excess weight can help lower CRP.
• Follow prescribed treatments: For conditions like autoimmune diseases or heart disease, ensure you’re taking medications as prescribed and following your doctor’s recommendations.

Which Specialist Should You Consult?

If your CRP levels are elevated, the specialist you should consult depends on the underlying cause of the inflammation. Here are the specialists most commonly involved in diagnosing and treating conditions related to high CRP levels:

• General Practitioner: The first point of contact for evaluating your overall health and making referrals.
• Cardiologist: If high CRP is linked to heart disease or cardiovascular risks, a cardiologist can help manage your heart health.
• Rheumatologist: For conditions like rheumatoid arthritis or lupus, a rheumatologist specializes in autoimmune and inflammatory disorders.
• Infectious Disease Specialist: If a serious infection is suspected, this specialist will help diagnose and treat the infection.