Phantom Menace: Does Seronegative Rheumatoid Arthritis Exist?
The quick answer is that, no, seronegative rheumatoid arthritis does not exist. However, this answer requires some explanation and a little background. Rheumatoid arthritis (RA) is a condition characterized by swollen, painful joints. It’s different from osteoarthritis, the type of joint damage that occurs naturally with aging.
RA occurs when your body’s immune system attacks the lining of your joints. Why this happens is still a mystery. Anyone can get RA, but it’s most common in women at middle age.
How Is RA Diagnosed?
There is no single test that your doctor can do to confirm that you have RA. A complete diagnosis includes an examination of the joints, possibly including X-rays, and blood tests. If your doctor suspects you might have RA, they’ll likely refer you to a specialist known as a rheumatologist for testing.
One of the blood tests that can help to confirm RA is the rheumatoid factor (RF) test. RF is a protein made by your immune system that can attack the healthy tissues in your body. Elevated levels of RF typically occur with autoimmune diseases like RA.
However, RF testing doesn’t give a definite diagnosis. Healthy people with no autoimmune disorders may have high RF levels in their blood. To further complicate the situation, people with RA can show normal levels of RF.
RF and Seronegative Results
The term seronegative is a general one. It refers to any blood test that comes back negative. For instance, if your doctor tests your blood for a virus and doesn’t find it, your results are seronegative.
People who have RA and seronegative results for the RF test are sometimes referred to as having seronegative RA or seronegative arthritis. For decades, doctors assumed this was just a type of RA, but now we know better.
It turns out that someone with many of the symptoms of RA but normal RF levels doesn’t have RA at all. Experts now classify several disorders that are similar to RA, but seronegative for RF, under the heading spondylarthropathy.
Spondylarthropathy is sometimes still referred to as seronegative arthritis, seronegative RA, seronegative spondylarthropathy, or BASE syndrome.
The Disorders of Spondylarthropathy
Many of the disorders that fall under the heading of spondylarthropathy were once thought to be variants of RA. They include:
- psoriatic arthritis
- reactive arthritis
- ankylosing spondylitis
- enteropathic arthritis
- Whipple’s disease
Each of these disorders is unique, but they share a common root. They’re all inflammatory, autoimmune disorders that cause arthritis in various parts of the body.
How Is Spondylarthropathy Different From RA?
These conditions may have arthritis in common, but there are some significant differences between RA and the class of diseases called spondylarthropathy. The first is that spondylarthropathy is more common in men.
Secondly, most spondylarthropathy conditions include complications in addition to arthritis, such as:
- inflammatory bowel disease (IBD)
- eye diseases
- canker sores
Arthritis in RA and Spondylarthropathy
RA and the conditions of spondylarthropathy also differ in the way the arthritis is experienced. Arthritis in RA occurs in the same joints on both sides of the body. However, arthritis is experienced asymmetrically in spondylarthropathy.
In spondylarthropathy, arthritis often occurs in the feet and ankles, and is not restricted to joints. It can flare up in the spine, and in the places where tendons attach to bones.
Treatments for Spondylarthropathy
Unfortunately, like RA, spondylarthropathy disorders have no cure. However, symptoms can be managed through treatments such as:
- topical creams for psoriasis
- antibiotics for eye infections
- dietary changes for inflammatory bowel disorders (IBDs)
Talk to your doctor about best options for treating your individual symptoms.
Rheumatoid Factor. (2013, July 9). Mayo Clinic. Retrieved August 1, 2013,
● Seronegative Arthritis. (2011). NYU Langone Medical Center, Division of Rheumatology. Retrieved August 1, 2013, from http://medicine.med.nyu.edu/rheumatology/conditions-we-treat/seronegative-arthritis
● Spondylarthritis. (2012). American College of Rheumatology. Retrieved August 1, 2013, from http://www.rheumatology.org/Practice/Clinical/Patients/Diseases_And_Conditions/Spondylarthritis_(Spondylarthropathy)/
● Spondylarthropathy. (2009, February 25). Cleveland Clinic. Retrieved August 1, 2013, from http://my.clevelandclinic.org/disorders/spondylitis/hic_spondyloarthropathy.aspx