Blood Tests for Inflammation and Autoimmune Disease
Blood tests for inflammation are designed to detect and measure levels of various markers of inflammation in the body. Inflammation is characteristic of a variety of diseases and health conditions, which makes these tests an important diagnostic tool. Here we'll get into the details of inflammation testing, including how these tests are done, what they look for, and how they can aid in detecting and diagnosing certain health issues, including infection and autoimmune disease, among others.
What does it mean when blood tests show inflammation?
When a blood test shows inflammation, this means that you are experiencing either acute or chronic inflammation somewhere in your body. Inflammation is a natural part of the body's immune response, aiding in the healing process when an injury, infection or tissue damage occurs. When the immune system responds normally, inflammation is generally short-lived, lasting only a few days or weeks. This is called acute inflammation, and common causes of it include:
- Cuts, scratches and other injuries
- Viral infections
- Bacterial or fungal infections
While acute inflammation is beneficial, chronic inflammation is harmful to the body. Chronic, or long-term, inflammation is when that immune response does not shut down after a few days or weeks as it should, continuing to cause inflammation for months or even years. Common causes of chronic inflammation include:
- Autoimmune responses, where the immune system attacks healthy tissues, mistaking them for pathogens
- Long-term low level exposure to an irritant or chemical
- Long-term low-level infections
Chronic inflammation gradually damages tissues and can lead to a number of chronic health problems and diseases, including rheumatoid arthritis, atherosclerosis, inflammatory bowel disease and some cancers, to name just a few.
Measures antinuclear antibodies to help assess for autoimmune conditions
Measures the level of C-reactive protein to assess for inflammation
Measures the level of C-reactive protein (CRP) to help assess risk for heart disease
The Creatine Kinase (CK) test measures the level of Creatine Kinase in the blood.
This blood test measures the amount of CCP antibodies in the body.
Measures the rate that red blood cells settle to assess for inflammation
High levels of homocysteine in the blood are related to a higher risk of coronary heart disease, stroke, Alzheimer's disease and osteoporosis.
Measures rheumatoid factor, a marker of inflammation and some types of arthritis
Measures the amount of thyroid peroxidase (TPO) antibodies to help understand the cause of thyroid disorders
What is a normal CRP level?
A blood test called the C-Reactive Protein (CRP) test is among the most common methods of assessing inflammation. C-reactive protein is produced by your liver and found in your blood. C-reactive protein levels rise in the blood when there is inflammation in the body, making it a good marker for detecting its presence. When you have CRP tested, C-reactive protein is measured in milligrams of CRP per liter of blood (mg/L). CRP levels that are below 3.0 mg/dL are considered normal.
What does a high C reactive protein mean?
C-reactive protein levels of more than 3.0 mg/dL are considered higher than normal. It is important to note that, since CRP levels can vary significantly from one day to the next, getting an accurate CRP level generally requires being tested twice, with the second test done two weeks after the first. High results on CRP inflammation tests means that you have inflammation somewhere in your body. This may be due to a short-term problem, like an infection or injury, or related to a long-term health condition or disease.
The CRP test is a non-specific test, which means it cannot be used alone to diagnose particular health problems or diseases. While this test can tell you and your healthcare provider that inflammation is present in your body, it cannot show exactly where inflammation is within the body or what is causing it. For that reason, a high CRP result typically prompts additional testing. Depending on what your doctor suspects may be at the bottom of your inflammation, this may include additional inflammation tests, such as:
- Erythrocyte Sedimentation Rate (ESR) – This blood test measures the rate that red blood cells settle. When inflammation is present, that rate is increased.
- Rheumatoid Arthritis (RA) Factor – A blood test that measures rheumatoid factor, a marker of inflammation and some types of arthritis.
- Creatine Kinase (CPK, CK) – This blood test measures levels of creatine kinase in the blood. Elevated levels can indicate muscle inflammation and other muscle problems.
Other tests may be done if your doctor feels that autoimmune conditions may be causing inflammation. Common examples of tests for autoimmune disease or activity include:
- Antinuclear Antibodies (ANA) – This test measures the level of antinuclear antibodies in the blood, which are antibodies produced by the immune system that attack the nucleus of healthy cells in the body.
- Cyclic Citrullinated Peptide Antibodies (CCP Antibodies) – This blood test measures levels of antibodies that attack cyclic citrullinated peptides (CCP) in the blood. These antibodies are often found in the blood of people who have rheumatoid arthritis.
- Thyroid Peroxidase (TPO) Antibodies – This test measures the level of thyroid peroxidase (TPO) antibodies in the blood, which are often found in people with autoimmune thyroid disease.
- Rheumatoid Arthritis (RA) Factor test – Measures the level of the rheumatoid factor (RF) in the blood, which is an autoantibody that attacks healthy tissues. RF is often present in people who have rheumatoid arthritis or other autoimmune diseases.
How can I lower my C reactive protein level?
The answer to that question depends largely on the exact cause of your high C-reactive protein levels. If inflammation is due to a clear underlying health issue, infections or autoimmune disease, for instance, treating those conditions typically lowers C-reactive protein levels. Other things that can help include controlling your weight, since being overweight or obese tends to increase inflammation and getting regular exercise, since sedentary lifestyles also tend to lead to increased inflammation. Dietary changes can help too, such as increasing fiber in your diet, which helps reduce inflammation, and decreasing sugars, starches, red meats, fatty foods and processed foods which tend to increase inflammation in the body. If you smoke, quitting can also help, as can lowering your intake of alcohol.