What Are Gottron Papules?

Gottron papules are red or violet bumps that form on the outside joints of the hand. They are caused by a rare inflammatory muscle disease called dermatomyositis.

In addition to classic skin changes, people with dermatomyositis usually develop gradual muscle weakness in the muscles closest to the body (e.g., shoulders and thighs). This can cause difficulties with getting up from a chair, climbing stairs, lifting things, and combing or brushing your hair.

Symptoms

Gottron papules are red or violet-colored bumps that occur on the top part of the hand, specifically the knuckles (called metacarpophalangeal joints) and the joints of your fingers (called interphalangeal joints).

Sometimes the rash—which causes an itchy or burning sensation and worsens when exposed to sunlight—extends onto the skin in between the joints.

Similar to Gottron papules, red or violet-colored patches may develop on the outside surfaces of other joints, like the back of the elbow, front of the knee, or outside part of the ankle.

Technically speaking, these rashes are called Gottron signs and not Gottron papules, because the rash is flat and not bumpy.

Causes

Gottron papules are essentially diagnostic for a disease of muscle inflammation called dermatomyositis.

The skin changes present in dermatomyositis (notably, Gottron's papules) may occur before or while the muscle weakness develops.

Experts have not teased out a precise cause behind dermatomyositis. They suspect that this disease occurs as a result of many factors coming together. For example, scientists have found that certain gene mutations (when the DNA sequence of a gene is changed) are associated with the development of dermatomyositis.

Immune system problems and environmental factors—such as sunlight exposure, viral infections, certain medications, and smoking—have also been linked to this disease.

Diagnosis

Many dermatologists can recognize Gottron papules by their classic appearance. During the skin examination, a healthcare provider will also look for other rashes associated with dermatomyositis.

For example, besides Gottron papules, a key skin finding seen in patients with dermatomyositis is the heliotrope rash, which is a violet-colored rash located on the upper eyelids and sometimes the cheeks and nose. Eyelid swelling often accompanies this rash.

Other skin changes seen in dermatomyositis include:

• Shawl sign: Violet or red patches over the back of the shoulders, upper back, neck, and sometimes the upper sides of the arms
• V sign: Reddening of the front of the chest (within the area of the skin that is normally exposed if a person wore a V-neck shirt)
• Nail changes: Reddening of the skin around the nail, along with the presence of dilated blood vessels (called telangiectasias)
• Scalp changes: Red, scaly (sometimes itchy) plaques may form on the scalp (they may resemble psoriasis or seborrheic dermatitis)
• Mechanic's hands: Scaling and cracking of the fingers and/or palms, along with skin thickening (this is a rare finding)

Besides a thorough skin examination, a skin biopsy may be performed (albeit rarely). This is because Gottron's papules can mimic other skin conditions, such as psoriasis or lichen planus.

With a skin biopsy, a healthcare provider removes a small piece of the skin where the rash is present. This skin sample is processed and examined under a microscope by a pathologist.

Finally, since Gottron's papules are a key indicator of dermatomyositis, other tests used to diagnose and evaluate this muscle disease are often performed.

These tests may include:

• Blood tests: To look for elevated muscle enzymes (e.g., creatinine kinase) and positive antibodies (e.g., anti-Mi2 antibody)
• Electromyography (EMG): To look for abnormal electrical activity in the muscles
• Magnetic resonance imaging (MRI) of the muscles: To look for muscle inflammation
• Muscle biopsy: To look for muscle inflammation

Treatment

The treatment of Gottron's papules entails taking a strong anti-inflammatory medication called a steroid (e.g., prednisone).

Since steroids can cause numerous harmful side effects, healthcare providers will aim to treat patients with the lowest dose for the shortest period of time possible.

In addition, to minimize the use of steroids, medications (called steroid-sparing agents) such as methotrexate or Cellcept (mycophenolic acid), are often given at the start of treatment.

A Word From Verywell

Gottron papules are a rare finding—so if you are concerned you have this skin change, please be sure to make an appointment with your healthcare provider, preferably a dermatologist. They can sort out your diagnosis and get you started on the right treatment plan.