Key Highlights:
- The CRP test measures C-reactive protein levels in the bloodstream, which increase in response to inflammation.
- This test can help diagnose infections, monitor autoimmune diseases, and assess cardiovascular risk.
- Preparing for the test may involve avoiding physical activity or certain medications beforehand.
- Normal CRP levels vary, but high levels may indicate serious infection, injury, or chronic disease.
- Understanding CRP test results is important for proper interpretation and management by healthcare professionals.
Introduction
The CRP test is an important marker. It tells us how much inflammation is present. This data can help detect certain medical problems. In this article, we’ll talk about the CRP test. We’ll discuss the tests, their impact on heart health, and how to prepare for it. We’ll also cover how to make sense of test results, and the test’s limits. Lastly, we will answer some frequently asked questions regarding this topic.
What is C-reactive Protein (CRP)?
C-reactive protein is a protein produced by the liver. It’s part of our body’s answer to inflammation. It acts as a marker for inflammation in the body. This includes infections, diseases of the immune system, and heart disease risk.
Overview of CRP Test
The Reasons Why this Test is Ordered?
A healthcare provider might order a CRP test for any of the following reasons.
- For detecting infections: With respect to infections, CRP levels go up.
- For keeping track of autoimmune diseases: Diseases of the immune system can make CRP levels rise. The CRP test help track how various therapies are working.
- For detecting inflammation: CRP levels can detect if inflammation is short-term or long-term. This information helps with diagnosing and making a management plan.
Types of CRP tests
There’s the regular CRP test and the high sensitivity CRP test, both are described below.
- Regular CRP test: This test checks how much CRP is in the blood. A high amount could mean an infection, injury, or long-term disease.
- High-sensitivity CRP test (hs-CRP): This test is more sensitive than the regular one. It can detect even small changes in CRP levels. This test mainly checks for heart disease risk. It helps estimate the chance of heart disease and heart attacks.
Did you know?
- High levels of C-reactive protein (CRP) may indicate a serious health condition causing inflammation. source: MedlinePlus
- Chronic inflammation, caused by conditions like autoimmune disorders or repeated tissue injury, can lead to elevated CRP levels. source: MedlinePlus
- CRP levels are typically low in healthy individuals, but can increase rapidly in response to inflammation. source: StatPearls
CRP Test and Heart Disease
CRP Levels and Heart Disease
Heart disease and inflammation are linked. CRP is a key marker here. High CRP levels can mean more risk of heart attacks. This is because they show there’s inflammation in the heart’s blood supply.
hs-CRP and Heart Disease Risk
The hs-CRP test finds even small changes in CRP levels. This makes it a handy tool. It gives an estimate of a person’s heart disease risk. Other risk factors help too, like family history, way of life, and overall health. Healthcare providers can then pick the right steps to avoid disease.
Preparing for the CRP Test
Getting Ready
Here’s what to do to prepare for a CRP test:
- Fasting: Normally, you don’t need to fast for a CRP test. However, if it’s with tests that need fasting, like cholesterol or glucose, follow your healthcare provider’s guidance.
- Medicine: Some drugs can change CRP levels. Tell your healthcare provider what medicines you’re on. This includes both over-the-counter and prescription drugs.
During the Test
Getting a CRP test means taking a blood sample. Usually, it’s from a vein in your arm. Here are the steps involved in the procedure.
- Collecting the sample: A healthcare provider will stick a needle into a vein to collect some blood.
- Time for the test: The blood draw is quick. It takes only a few seconds. You can go back to normal activities right away.
Interpreting CRP Test Results
1. Normal CRP Levels
Knowing the normal range for CRP levels helps to make sense of test results. Normal levels can change based on which laboratory did the test. Usually, the normal range is as follows.
- Regular result: Below 3.0 mg/L of blood
- A mildly high: 3.0–10.0 mg/L of blood
- Moderately high: 10.0–100.0 mg/L of blood
- Severely high: Above 100.0 mg/L of blood
What changes normal levels?
Things like being pregnant, weight, smoking, not moving much, and some drugs can change normal CRP levels.
2. High CRP Levels
Why CRP Might Be High?
High CRP levels can result from a serious infection, a major injury, long-term disease, or autoimmune conditions like rheumatoid arthritis or lupus.
How to Use High CRP to Diagnose?
The CRP test shows if there’s inflammation, but it can’t find the exact cause. Healthcare providers will need more tests and examinations to confirm the diagnosis. Along with the CRP results, they can make a more accurate diagnosis.
3. Results of hs-CRP test
Checking Heart Disease Risk
The hs-CRP test gives a person’s heart disease risk based on their CRP:
- Low risk: Less than 2.0 mg/L of blood
- Medium risk: Between 2.0 and 3.0 mg/L of blood
- High risk: More than 3.0 mg/L of blood
Possible Life Changes
A hs-CRP test can show a higher risk of heart disease. In this case, lifestyle changes might be advised, like:
- Eating healthier
- Increasing physical activity
- Stopping smoking
- Lowering stress
Also Read: CRP Test vs ESR Test: Understanding the Differences and Significance
Risks and Limits of CRP Test
Risks with Blood Tests
Blood tests are mostly safe, but they can cause slight discomfort. Small risks include bruising, swelling, or a lump at the test site. Also, feeling dizzy or passing out.
Limits of CRP Test
The CRP test does have some limits:
- Not specific: The test identifies inflammation but can’t find the exact cause for it.
- Accuracy: Lots of factors can change CRP levels. So, interpreting the results needs more tests and checking.
Also Read: CRP Blood Test Cancer: Understanding its Significance in Diagnosis and Treatment
Conclusion
Knowing how to understand CRP test results is key for the right care and management. With other tests and health professional guidance, the CRP test can give key insights into your health. Working with your healthcare provider, reading your CRP results, and making any needful life changes may let you take charge of your health. This will help move towards better well-being.
Frequently Asked Questions (FAQs)
What happens if a person’s C reactive protein is high? A high level of C-reactive protein in the blood points to inflammation. This could be due to a serious infection, injury, or long-term disease. Your healthcare provider may suggest further tests to find out what is causing this.
How high a level of C reactive protein is worrying? A result of 8 mg/L or 10 mg/L or higher is seen as high. It could mean there’s a lot of inflammation. However, it depends on the laboratory doing the test, as ranges can vary from one laboratory to the other.
What infections make CRP high? Sever infections, like bacterial or fungal ones, can make CRP levels jump. Lung infections like pneumonia, flu, and adenovirus infections can also raise CRP.
What’s normal for CRP level? A typical normal level for CRP is below 3.0 mg/L. Normal ranges can change between laboratories. Above this range, levels may be seen as high. This means there’s inflammation.
What if my CRP report is high? If your CRP is high, get in touch with your healthcare provider. They can help understand the results. They can guide you on the right management plan or they might ask for more tests to find the root cause.
What’s a bad CRP level? A CRP over 100.0 mg/L is usually seen as very high. It could mean an acute bacterial infection or other conditions that cause a lot of inflammation.
What kind of inflammation makes CRP high? Lots of types of inflammation can push CRP higher. These include infections, injuries, long-term diseases, and autoimmune diseases (like rheumatoid arthritis or lupus).
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Medically reviewed by Dr. Nayana Shetty 
Last updated: Apr 17, 2024
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