Adults with rheumatoid arthritis (RA) are generally classified during diagnosis as seropositive or seronegative RA based on the presence of biomarkers found in the blood. Regardless of classification, symptoms tend to be similar.
When children are diagnosed with RA, it is called juvenile RA, juvenile chronic arthritis, or juvenile idiopathic arthritis (JIA). The condition may or may not disappear as the child grows up.
Rheumatoid Arthritis types
Between 60 to 80 percent of people with RA are diagnosed as seropositive. If your blood test shows the presence of anti-cyclic citrullinated peptides (anti-CCPs), proteins that provide evidence of an autoimmune reaction, you are considered seropositive. Anti-CCPs can show up in the blood five or even 10 years before RA symptoms appear. Presence of rheumatoid factor (RF) in the blood may also be used in classifying someone as seropositive.
If you are diagnosed with RA, but anti-CCPs and RF are not found in your blood, you will be classified as seronegative.
People with seronegative RA often have a milder disease course than those with seropositive RA.
Read more about how RA is diagnosed.
Juvenile rheumatoid arthritis
Similar to other types of RA, juvenile RA symptoms include swelling, pain, and stiffness of the joints. While symptoms may go into remission with age, some children will continue to have RA-related symptoms in adulthood. In addition to the joint symptoms, juvenile RA may also interfere with a child’s growth and bone development or cause inflammation in the eyes or lymph nodes.
There are several subtypes of juvenile RA. Systemic onset JIA begins with repeated high fevers and a salmon-colored rash and may involve inflammation of organs in addition to joints. Oligoarticular JIA involves fewer than five joints, while polyarticular JIA involves five or more joints. Enthesitis-related arthritis, also called spondyloarthritis, involves the spine and ligaments.
If I’m diagnosed with seronegative RA, could I later become seropositive?
It is unlikely for someone with seronegative RA to develop seropositive RA. However, someone initially diagnosed with seronegative RA may eventually be diagnosed with a different condition such as psoriasis or chronic gout.