Have you ever wondered how your health care provider can determine if you are fighting off an infection or experiencing inflammation?
One useful test that helps in this process is called the CRP test. CRP stands for C-reactive protein, and it plays an essential role in your immune system’s response to inflammation.
Your provider uses this test to help diagnose and monitor several different causes of inflammation, such as infections and autoimmune conditions.
Here we answer six important questions about CRP testing and if you could benefit from it.
What is CRP?
C-reactive protein (CRP) is produced by the liver and released into the bloodstream when there is inflammation in the body. It acts as a marker or a signpost for inflammation, alerting health care professionals to a potential problem.
“Any time your body encounters stress, which can be from an infection (like viruses or bacteria), surgery, cancer or inflammation, the body produces CRP,” said Kristen Young, DO, a rheumatologist with Banner – University Medicine. “CRP is a non-specific marker of inflammation and tissue damage.”
What does the CRP test measure?
The CRP test measures the levels of C-reactive protein in your blood.
“The CRP test is primarily used to identify and monitor inflammation and track the progress of treatment, especially in rheumatic diseases like rheumatoid arthritis,” Dr. Young said.
When should you take the CRP test?
Your provider may recommend the CRP test if you’re experiencing symptoms such as fever, fatigue, joint pain or swelling, which may suggest inflammation.
Inflammation can be caused by a variety of conditions, including:
- Severe bacterial infections like sepsis
- Fungal infections like candidiasis
- Autoimmune diseases like rheumatoid arthritis (RA)
- Inflammatory diseases like gout, Crohn’s disease, colitis or inflammatory bowel disease
- Bone infections like osteomyelitis (infection of the bone)
“The CRP test is increasingly being used to determine the risk for heart disease,” Dr. Young said. “With heart disease, CRP levels tend to be elevated and continue to increase as the disease progresses.”
What are the pros and cons of CRP testing?
The benefits of CRP testing
- Quick and easy: The CRP test is a simple blood test that can be done in your provider’s office, clinic, hospital or lab facility. It should take less than five minutes.
- Non-specific marker: CRP is a non-specific marker, which means it can indicate the sign of inflammation but not the exact cause. This flexibility allows providers to use the test for various conditions.
- Monitoring treatment: The test can be used to monitor the effectiveness of treatments for inflammatory conditions. If the levels decrease over time, this suggests the treatment is working.
The drawback of CRP testing
- Lack of specificity: While the test can indicate inflammation, it can’t pinpoint the exact cause. Further tests may be required to identify the underlying condition.
- Normal levels can vary: Levels of CRP can fluctuate in response to various factors, such as age, gender and overall health. Interpreting the results requires considering these individual differences.
How do I interpret the results?
CRP levels are measured in milligrams per liter (mg/L) or milligrams per deciliter (mg/dL). Higher CRP levels usually indicate the presence of inflammation.
“However, it’s important to remember that CRP alone can’t diagnose a specific condition,” Dr. Young said. “Depending on your symptoms and medical history, your provider will interpret the results alongside other tests and examinations to make an accurate diagnosis.”
Although “normal” CRP levels can vary from lab to lab, it is generally accepted that a value of 8 mg/L to 10 mg/L (0.8 mg/dL to 1.0 mg/dL) or lower is normal. Most healthy adults have a level lower than 3 mg/L (0.3 mg/dL).
“A CRP test result of more than 10 mg/L is generally considered a marked elevation and may indicate signs of an infection or injury,” Dr. Young said. “Higher CRP can indicate severe acute infection or inflammation.”
What is the treatment for high CRP?
If your CRP results are slightly elevated (borderline), it doesn’t mean you necessarily have a medical condition that needs treatment. Your provider may take a wait-and-see approach and retest to see if the results change.
“There are many things like smoking, obesity, surgery or a recent injury that can cause your CRP levels to rise slightly,” Dr. Young said.
If your CRP results are high or severely high, your provider will discuss them with you and develop a plan to investigate further or treat them. Depending on your situation, this may involve additional tests, imaging studies or consultations with specialists.
Some treatment options for high CRP levels may include taking medication like antibiotics and statins and/or conservative measures like eating a balanced diet, regular exercise, smoking cessation and weight loss.
“There is no specific treatment for a high CRP, but we try to understand the cause and treat what is causing that elevation,” Dr. Young said.
“Many times, the underlying cause is obvious – like surgery or infection, other times, it takes more monitoring and evaluation to understand,” he said. “When it is not clear, we recommend screening for age-appropriate cancers, infections and autoimmune disease.”
Takeaway
The CRP test is a valuable tool that helps health care providers assess inflammation in the body. By measuring C-reactive protein levels, they can identify potential problems and monitor the effectiveness of treatments.
While the test has its limitations, it provides valuable information that can aid in the diagnosis and management of various conditions.
Consult with your provider to fully understand your test results and determine the best course of action for your health. To find a Banner Health specialist near you, visit bannerhealth.com.
