Finding a bump under your skin can be an alarming experience. But for people diagnosed with rheumatoid arthritis (RA), it’s not entirely uncommon. Nearly a quarter of people with RA also experience rheumatoid nodules — bumps that form in the soft tissues near affected joints, tendons, and visceral organs.
Here, we’ll discuss what rheumatoid nodules are, why they form, and what people with rheumatoid arthritis can do to address them.
Rheumatoid nodules are inflammatory bumps that develop in certain parts of the body. The nodules are necrotizing, which means they cause tissue death (necrosis) where they form.
Rheumatoid nodules tend to appear under the skin at bony pressure points, such as the elbows, lower spine (sacrum), feet, and fingertips. However, nodules are not limited to these areas. They may also appear in the soft tissues around the joints, as well as in the tendons, eyes (sclera), lungs (pleura), heart (myocardium), and vocal cords.
These raised bumps can vary significantly in size, typically ranging from 2 millimeters to 5 centimeters. They are composed mostly of fibrin (a protein that often appears after tissue damage) and dead skin cells. Nodules tend to be round (though some may have wavy borders) and often shift position when poked. The number of rheumatoid nodules that appear varies from person to person. Some people may only have one, while others might have several in different locations.
These lesions can appear quickly, too. “I had a nodule show up on my pinky and thumb overnight,” wrote a member of myRAteam.
By themselves, rheumatoid nodules generally don’t cause any concerning symptoms. The bumps don’t typically feel tender or hurt, even when pressed. However, there are inconvenient and painful exceptions.
Nodules that form a connection with subcutaneous (under the skin) tissues or tendons can root in place and become sensitive. Nodules that grow to a substantial size might also compress nerves or blood vessels, causing pain or limiting a person’s range of motion.
Other times, nodules can be inconvenient due to their location. For example, lesions on the feet can make walking difficult or cause gait changes that put added stress on the knees, hips, or lower back, leading to soreness or pain.
Nodules can also cause other inconveniences. “I have a few healthy-sized nodules on my feet near the balls of my feet and big toes,” wrote a myRAteam member. “I normally wear a size 10 to 11, but now I have to buy a 12, which, in some cases, means special ordering.”
Rheumatoid nodules appear as the result of rheumatoid arthritis — a chronic inflammatory disorder that occurs when a person's immune system mistakenly identifies the synovium, the flexible membrane that lines the joints, as a threat. Over time, misdirected attacks from antibodies can result in the characteristic symptoms of rheumatoid arthritis, including inflammation, bone erosion, and joint deformity.
Rheumatoid nodules usually form several years after RA onset. Rheumatology experts aren’t entirely sure why these lumps form, although individuals with high rheumatoid factors (proteins that cause autoimmune diseases, like RA and Sjögren’s syndrome) in their blood are more likely to develop nodules. People who smoke or have severe rheumatoid arthritis may also have an increased risk of developing rheumatoid nodules.
Methotrexate, an immune-modulating drug used to treat rheumatoid arthritis, can also prompt nodule growth — a side effect called accelerated nodulosis. As the name suggests, accelerated nodulosis causes the fast-paced development of rheumatoid nodules. This phenomenon frequently leads to symptoms in the hands.
One myRAteam member shared how they saw their dermatologist after observing nodules on their fingers had grown larger. A test showed “that the nodules were caused by taking methotrexate,” the member shared. “I stopped taking methotrexate, and the nodules are going away.”
Generally, stopping the methotrexate treatment or incorporating other therapies into a person’s RA drug regimen will slow or reverse nodule growth. That said, you should never stop taking your RA medication without first consulting your rheumatologist, as doing so could negatively affect your short- and long-term health outcomes.
Doctors will likely be able to diagnose rheumatoid nodules with a simple physical exam, so long as you have a demonstrated history of rheumatoid arthritis. In some cases, your physician may confirm a diagnosis by running blood tests to check your rheumatoid factor or taking a skin sample (biopsy) of a mature lesion.
Advances in rheumatoid arthritis care have drastically reduced the number of people who experience and require treatment for rheumatoid nodules. New, highly effective medications for RA have led to a reduction in the number of people developing rheumatoid nodules.
Rheumatoid nodules don’t always require treatment. Nodules that aren’t tender and don’t cause pain may be little more than a cosmetic annoyance. However, if lesions do form in locations that restrict your movement or cause other physical problems, your health care provider may recommend treatment.
Taking medications known as disease-modifying antirheumatic drugs (DMARDs) can shrink nodules and limit further growth. Alternatively, your doctor might suggest injecting corticosteroids to reduce local inflammation. Surgical removal is also an option, although your doctor may advise against surgery, as it can be invasive, and nodules often grow back after removal.
You and your doctor should also keep an eye out for infection. Nodules in high-pressure areas, such as the feet, are at higher risk of developing infections. If you start to see signs of discoloration, swelling, or itching, ask your doctor for medical advice. If those symptoms are the result of an infection, you may need to take antibiotics to alleviate them.
Rheumatoid arthritis is a uniquely challenging condition. It’s not always easy to navigate the day-to-day hurdles it poses alone. Fortunately, you don’t have to.
On myRAteam, the social network for people with RA, more than 146,000 people from across the world come together to ask questions, offer advice and support, and share stories of life with rheumatoid arthritis.
Have you developed rheumatoid nodules with RA? Share your experience in the comments below or by posting on myRAteam.