What Is Seropositive RA?
Rheumatoid arthritis (RA) is often called seropositive or seronegative. Seropositive refers to the presence of RA autoantibodies in the blood. Seronegative means these autoantibodies are not in the blood.
Both serotypes cause similar symptoms and have similar treatments. Doctors find that people with seropositive RA show worse symptoms and/or more complications than those with seronegative RA. However, there are many exceptions.1
What is seropositive RA?
If you have seropositive RA, your body makes autoantibodies called rheumatoid factor (RF) and/or anti-cyclic citrullinated peptides (anti-CCP).
Autoantibodies are proteins of autoimmune diseases. They target other proteins in your body. This causes tissue damage. If you have RA autoantibodies, you may have seropositive RA.1
How is seropositive RA diagnosed?
You will get a blood test to look for RA autoantibodies. Your doctor will also evaluate your joints. You may get X-rays or an ultrasound to look for bone erosion or nodules.
Your doctor will ask if you have RA symptoms. RA symptoms include:1
- Joint pain or swelling that affects many joints
- Morning stiffness that lasts more than 30 minutes
- Tingling or numbness in the hands
- Bone or cartilage damage
RA autoantibodies trigger the immune system. Your body may become inflamed as a result. You may have symptoms of inflammation including:2
- Body aches
- Depression and/or anxiety
- Gastrointestinal issues
- Changes in weight
Typically, RA symptoms last more than 6 weeks. Symptoms may come and go. An RA diagnosis is made using the results of the physical exam and bloodwork. If you have symptoms and RA autoantibodies, you may have seropositive RA.1
Blood work can reveal RA autoantibodies and chronic inflammation. For seropositive RA, autoantibodies can typically be found in the blood if symptoms are present. Blood work is often used to check for rheumatoid factor, anti-CCP, and inflammation.
If you test positive for RF, you have a 70 to 80 percent chance of having RA. Having an immediate family member who is RF-positive raises your chance of having RA. In seropositive RA, RF is found in blood work within a year after symptoms start. You can be RF positive and have a condition other than RA.1-3
Anti-CCP is an anti-citrullinated protein antibody. This test is also known as ACPA, CCP antibody, and citrulline antibody. It is more specific for RA compared to RF. About 98 percent of those with anti-CCP have RA. Anti-CCP can appear in your blood 10 years before symptoms start.1,3-5
C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are blood tests that help doctors detect inflammation. Since RA causes chronic inflammation, these tests are useful. Your doctor may also want to test for other autoimmune diseases.1,4
Disease-modifying antirheumatic drugs (DMARDs), steroids, and nonsteroidal anti-inflammatory drugs (NSAIDs) treat seropositive RA. Symptoms can be controlled by these drugs. This is especially true if drugs are started before RA progresses further. Physical therapy may help with mobility. In some cases, surgery can lessen joint pain.6-7
Anti-CCP auto-antibodies have been linked to severe joint damage. You may get rheumatoid nodules or need surgery to relieve pain. Anti-CCP and RF cause bigger and more numerous bone erosions. Being positive for both causes the worst erosions. Vasculitis, rheumatoid lung, and heart disease are also possible complications of seropositive RA.1,7-9
Differences in outcomes
For people with seropositive RA, joint damage can be worse. There is a higher rate of RA-related complications compared to seronegative RA. Seronegative RA symptoms may be worse upon diagnosis, but this could be because it is harder to diagnose.
Studies are ongoing to determine how antibody status might affect responses to different medicines. More research is also being done to sort out the differences between seronegative and seropositive RA.5,7,8-10
It is important to note that serotype alone does not determine the severity of RA. Many other factors affect the progression of RA. However, symptoms can be bad enough to interfere with your daily activities. There is no cure for RA, but regular visits to your doctor can help manage symptoms.
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