Rheumatoid Nodules on the Scalp

Rheumatoid arthritis (RA) is chronic condition that affects the joints, specifically the synovium, which is the lining of the joints. The disease involves flare-ups of inflamed joints followed by periods of time when there are little or no symptoms. Rheumatoid arthritis can result in permanent deformities if the the disease is left untreated, leaving knotted, joints. Rheumatoid nodules are another symptom of this disease, and they appear at pressure points such as the hands, feet and scalp.

Formation

• Rheumatoid nodules form in people with rheumatoid arthritis who have high levels of the autoantibody rheumatoid factor (RF) in their blood. Rheumatoid nodules most commonly form in places where the skin is exposed to constant irritation, such as the fingers and heels. Scalp nodules are much less common. The nodules usually don't form until the disease has progressed for at least a year, and they only occur in 25 percent of people with rheumatoid arthritis.

Characteristics

• Rheumatoid scalp nodules range in size from as small as a pea to as large as a walnut. On rare occasions, nodules can grow as large as a fist. They're skin colored and firm to the touch. The nodules are made up of different types of blood cells that surround a core of protein fibers. Most nodules are painless, especially those that appear on the scalp because they're not exposed to as much irritation as those on the feet or hands.

Causes

• The reason rheumatoid nodules form isn't completely known. The RF in the blood is a major factor, but doctors haven't confirmed this autoantibody is the only origin. Nodules on the scalp may form because of the constant exposure of the back of the scalp to pressure and irritation. Skin and bone rub together, causing blood vessels to break and autoantibodies to pool in the area. Some RA studies have shown that smoking can cause nodules. Researchers also believe the drug methotrexate contributes to nodule formation.

Treatment

• Rheumatoid scalp nodules are usually small and harmless, requiring no treatment. If the nodules become infected or painful, they may need to be reduced in size or removed. Disease modifying anti-rheumatic drugs (DMARDs) and steroids are both used to shrink scalp nodules. Rheumatoid nodules can also be surgically removed. Surgery is performed if the nodules become infected or the patient is uncomfortable with the appearance of very large nodules. The main disadvantage of surgery is the nodules can grow back in the same spot within a few months of removal. The best way to manage nodules on any part of the body is to monitor any changes in them and report them to a doctor.