Seronegative rheumatoid arthritis and fibromyalgia may be more closely linked than we think, according to 2016 study published in American College of Rheumatology. Researchers of the study found strong evidence that seronegative rheumatoid arthritis and fibromyalgia are connected.
1. What is Seronegative Rheumatoid Arthritis?
There are two main subgroups of rheumatoid arthritis (RA), seronegative rheumatoid arthritis and the more common seropositive rheumatoid arthritis.
In usual cases of RA, patients would score positive for rheumatoid factor and/or anti-citrullinated peptides (CPP) antibodies. This means that he/she is seropositive and therefore carries the antibodies which causes inflammation in the joints. Patients that are seropositive suffer more severely in joint symptoms such as pain, damage, deformities and even inflammation in adjacent areas.
On the other hand, RA patients who experience characteristic symptoms of RA but test negative for rheumatoid factor and/or anti-citrullinated peptides (CPP) antibodies are diagnosed with seronegative RA. These patients either do not or do not yet carry sufficient antibodies. However, many of them can develop antibodies years after their early diagnosis, hence changing their condition to seropositive RA.
Many consider Seronegative RA to be the less severe form of RA. However, studies have shown that as the disease progresses, it can be comparable to seropositive RA. Therefore, it can be tricky to categorise RA into sub-types and to derive a clear diagnosis.