A number of diseases mimic the symptoms ofrheumatoid arthritis(RA), anautoimmuneform of arthritis.
These include bacterial joint infections, inflammatory diseases, other autoimmune diseases, andother forms of arthritis.
Ruling out conditions that mimic RA is central to thediagnosis of RA.
Verywell Health / Hilary Allison
This article describes 14 conditions that mimic rheumatoid arthritis along with comorbid conditions that commonly occur alongside RA.
Verywell Health / Hilary Allison
Did You Know?
Osteoarthritis
Osteoarthritis(OA), is a degenerative joint disease that can be similar to RA.
It is the most common form of the disease, often referred to as “wear-and-tear arthritis.”
Autoimmune diseases are those in which the body’s immune system attacks its own cells and tissues.
Sjogren’s can also affect other organ systems as well, most notably the joints.
Joint pain is one of the more common symptoms of Sjogren’s.
Multiple joints are typically affected, causing sudden and severe episodes of pain, swelling, and tenderness.
As with RA, joints on both sides of the body are affected at the same time.
Moreover, many people with Sjogren’s also have RA, further complicating the diagnosis.
The differentiation of Sjogren’s and RA requires an expert review of the various tests and symptoms.
PSA can closely mimic RA, but can often be differentiated through blood tests.
Since high levels of RF and anti-CCP are typically present in RA, these results are consideredseropositive.
PsA can have low levels of RF but no anti-CCP antibodies, making these indicatorsseronegative.
Both RA and PsA can start in the fingers and toes.
However, PsA and otherspondyloarthropathiesare more likely to go on to affect the spine and thesacroiliacjointsthan RA.
Viral arthritis can often be distinguished from RA by a rash and a history of exposure to specific viruses.
Your healthcare provider can take blood work to rule out different viral and bacterial causes of joint pain.
Treatment for viral arthritis is normally focused on pain management.
AndHIV-triggered arthritiscan be relieved with combination antiretroviral therapy.
Most cases of viral arthritis resolve on their own after several weeks.
If you might have this condition, the test is usually repeated in about six weeks.
Fibromyalgia
Fibromyalgia, a chronic pain condition, can be misdiagnosed as RA or another rheumatic condition.
Fibromyalgia also differs from RA because it causes:
Fibromyalgia can be difficult to diagnose.
Gout
Crystal-deposition diseases likegoutandpseudogoutare often mistaken for RA.
With these conditions, uric acid crystal deposits settle around affected joints, resulting in inflammation and tissue damage.
A gout attack commonly affects the large toe and lasts for three to 10 days.
Over time, gout attacks can become more frequent, last longer, and may not resolve.
This can lead to chronic gouty arthropathy, which can cause erosions and joint destruction.
Previously known as Reiter’s syndrome, reactive arthritis is in the family of seronegative spondyloarthropathies.
Symptoms generally appear within a month of a bout ofdiarrheaor agenital infection.
A blood test can identify bacterial infections, such asChlamydia trachomatis,Campylobacter,Salmonella,Shigella, orYersinia.
sparked by overuse or injury, the condition causes joint pain and inflammation that can be mistaken for RA.
Diagnosis is based on physical examination and imaging tests such as X-rays or MRIs.
Your healthcare provider may sample fluid from the swollen area to rule out an infection as well.
Characterized by tiny, grain-like lumps (granulomas), sarcoidosis can manifest with synovitis in several joints.
RF can be positive with this condition.
Like RA, sarcoidosis onset typically occurs between ages 30 and 50.
Other characteristics of sarcoidosis that help to distinguish it from RA include:
Sarcoidosis is formally diagnosed through biopsy.
These conditions affect joints and might mimic RA.
A key difference is that GCA commonly presents with headaches.
A detailed medical history can help distinguish PMR or GCA from RA.
It’s most often brought on by a mutation in theHFEgene.
The condition is uncommon in people of Asian or African ancestry.
Other causes include severe liver disease and receiving multiple blood transfusions.
Hemochromatosis can cause arthritis, among other problems.
The joint pain notably affects the knuckles of the index and middle fingers.
The joints may be swollen and have reduced range of motion, but are not inflamed.
Large joints such as the knees, hips, ankles, elbows, and shoulders may also be painful.
If you aren’t improving with treatment, talk to your healthcare provider.
You might need additional testing or a referral to arheumatologistor other specialist.
Ensuring an accurate diagnosis is essential for finding a treatment that works for you.
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