Dermatitis herpetiformis is an extremely itchy rash consisting of bumps and blisters. The rash is chronic (long-term), which means it continues over a long period.
Dermatitis herpetiformis usually begins in people age 20 and older. Children can sometimes be affected. It is seen in both men and women.
The exact cause is unknown. It is an autoimmune disorder. There is a strong link between dermatitis herpetiformis and celiac disease. Celiac disease is an autoimmune disorder that causes inflammation in the small intestine from eating gluten. People with dermatitis herpetiformis also have a sensitivity to gluten, which causes the skin rash. About 25% of people with celiac disease also have dermatitis herpetiformis.
- Extremely itchy bumps or blisters, most often on the elbows, knees, back, and buttocks
- The rash is usually the same size and shape on both sides
- The rash can look like eczema
- Some people may have scratch marks and skin erosions instead of blisters
Most people with dermatitis herpetiformis have damage to their intestines from eating gluten. But only some have intestinal symptoms.
Exams and Tests
In most cases, a skin biopsy and direct immunofluorescence test of the skin are performed. The health care provider may also recommend a biopsy of the intestines. Blood tests may be ordered to confirm the diagnosis.
An antibiotic called dapsone is very effective.
A strict gluten-free diet will also be recommended to help control the disease. Sticking to this diet may eliminate the need for medicines and prevent later complications.
Drugs that supress the immune system may be used, but are less effective.
The disease may be well-controlled with treatment. Without treatment, there may be a significant risk of intestinal cancer.
Thyroid disease may be found in many people with dermatitis herpetiformis. People with dermatitis herpetiformis are also more likely to develop certain cancers of the intestines. The drugs used to treat dermatitis herpetiformis can also have side effects. Blood tests will be needed to check the levels of these drugs in the body.
When to Contact a Medical Professional
Call your provider if you have a rash that continues despite treatment.
There is no known prevention of this disease. People with this condition may be able to prevent complications by avoiding foods that contain gluten.
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