C-Reactive Protein or CRP is a type of substance that is produced in the liver as a response to inflammation within the body. When a person suffers from any kind of injury or infection, it often leads to damage of the tissue. This damage causes inflammation within the body, triggering the body’s immune system to safeguard itself by sending a "response team" of proteins called "acute phase reactants." CRP is one of these proteins.
What Is C-Reactive Protein Test?
The C-Reactive Protein or CRP test is a type of test that analyses the concentration of the C-Reactive protein within the blood. This test is of two types, namely high-sensitivity C-reactive protein (hs-CRP) and ultra-sensitive C-reactive protein (us-CRP). A high level of CRP in the blood usually suggests intense inflammation which can occur due to a variety of health conditions and infectious diseases. In most cases, the hs-CRP is conducted to analyze presence of cardiovascular anomalies.
Why Is It Done?
A CRP test is usually done to find out the actual cause of the inflammation that triggers the particular protein. It is used for analyzing the given conditions:
- Bacterial infections, such as sepsis, pneumonia or tuberculosis
- A fungal infection
- Pericarditis, which is inflammation of the lining of the heart
- Gastrointestinal inflammation or infection in the form of Inflammatory bowel disease, Ulcerative colitis or Crohn’s disease
- An autoimmune disorder such as lupus or rheumatoid arthritis
- An infection of the bone called osteomyelitis
- Organ or tissue injury
When Should You Go For A CRP Test?
Although there are no particular symptoms that might suggest a need for a CRP Test. But it is usually done if you notice any of the symptoms from an underlying health condition like fever, chills, rapid heart best, rapid breathing, headache, sudden weight loss, unexplained exhaustion, insomnia, indigestion, nausea and vomiting. People who should go for CRP test include those who are suffering from the following health conditions:
- High cholesterol
- High blood pressure
- Diabetes mellitus
Even people with older age, or those who follow an extreme unhealthy lifestyle with little to no exercise, consume excessive amounts of alcohol or smoke too much tobacco are at higher risk of getting inflammation. Hence to avoid further complications, they should go for a regular health check-up which includes a CRP test as well.
In the case, where you are already suffering from an inflammation, regular CRP test measures the amount of protein in the blood which determines inflammation levels and thus helps in monitoring the treatment being employed.
How To Administer The CRP Test?
No specific measures are mandatory before the CRP test. A person can eat and drink normally both before and after taking the test. However, people going for a high-sensitivity CRP (hs-CRP) test are likely to undergo other blood tests along with it, and these may require fasting for 9–12 hours beforehand. Hence one should take proper suggestions from the doctor before going for the test.
It is usually conducted by a pathologist or doctor. The trained personnel usually wraps an elastic band around the arm, causing the veins to bulge out slightly. The practitioner then sterilizes the particular area and then inserts a small needle into the vein and collects the blood in a sterile vial. Once the blood is drawn, he or she removes the elastic band and asks you to put slight pressure on the puncture site to stop any leakage of blood and allow it heal fast.
Are There Any Side Effects Of The CRP Test?
There are usually no reported side effects from taking a CRP test apart from slight pain and inflammation at the puncture site that too only for some time after which it usually subsides on application of an ice pack or on its own. In very rare case scenarios, there were reports of excessive bleeding, dizziness or light headedness and bruising and infection at the puncture site.
How To Interpret CRP Test Results?
A detailed blood report determines the level of CRP found in your blood. In general, a low C-reactive protein level is better than a high one, because it usually indicates less inflammation in the body.
The C-reactive protein is chiefly measured in milligrams of CRP per liter of blood (mg/L).
A CRP reading less than 1 mg/L indicates you’re at low risk of cardiovascular disease.
A reading ranging between 1 and 2.9 mg/L signifies you’re at intermediate risk.
A reading greater than 3 mg/L ascertains you’re at high risk of cardiovascular disease.
If the reading is above 10 mg/L, the report usually signals a need for further testing to determine the cause of such significant inflammation in your body. This extreme high reading may indicate:
- Arthritis flare-up
- Osteomyelitis, a bone infection
- Infections like pneumonia
- Inflammatory Bowel Disease
- Autoimmune diseases like lupus, or connective tissue disease
- Certain cancerous conditions, like lymphoma
It should be kept in mind that CRP levels may also get elevated due to consumption of birth control pills or other medications. In case of pregnancy, high CRP values may be an indicator for complications, but further studies and tests are necessary to fully understand the role of CRP during pregnancy. Hence, before going for the test, speak freely about any medical condition you are already suffering from since it can skew the test results.
In any case, the CRP test does not explain the cause of particular location of the inflammation. For that the doctor may suggest follow-up diagnostics to find out the specific cause.
A CRP test is highly significant to predict cardiovascular disease beforehand based on its correlation with the other known cardiac risk factors and their role in the formation of atherosclerosis. Hence if you notice any kind of inflammation, go for a CRP test to find out the cause of it.