Dermatitis herpetiformis (DH) is a chronic disease of the skin marked by groups of watery, itchy blisters that may resemble pimples or blisters. The ingestion of gluten (from wheat, rye, and barley) triggers an immune system response that deposits a substance, lgA (Immunoglobulin A), under the top layer of skin. IgA is present in affected as well as unaffected skin. DH is a hereditary autoimmune gluten intolerance disease linked with celiac disease. If you have DH, you always have gluten intolerance. With DH, the primary lesion is on the skin, whereas with celiac disease the lesions are in the small intestine. The degree of damage to the small intestine is often less severe or more patchy than those with celiac disease. Both diseases are permanent and symptoms/damage will occur after consuming gluten.
The lgA deposits under the skin result in eruptions of red raised patches of skin, similar to the beginning of a pimple, that can develop into small watery blisters. The itching and burning of the eruptions are severe and the urge to scratch them is intense. Scratching will further irritate the eruptions. Eruptions commonly occur on pressure points, such as around the elbows, the front of the knees, the buttocks, back face, and scalp but can appear anywhere on the body. Eruptions are usually bilateral - occurring on both sides of the body. 60% of those diagnosed are men and the most common age at diagnosis is 15 to 40 years old. Although it is uncommon to diagnose young children with DH, we are seeing more cases of early childhood DH.
Your dermatologist will take a small biopsy of the unaffected skin very close to an eruption or eruption site. The presence of IgA deposits confirms a diagnosis of DH. Sometimes the dermatologist may also want you to have blood work for celiac disease and see a gastroenterologist.
Just as with celiac disease, strictly following a gluten-free diet for life is the only complete treatment. It may take two or more years on a gluten-free diet for the lgA deposits under the skin to clear. Your doctors may prescribe medications for immediate relief from the itching and burning eruptions. The most common medication used is Dapsone. This medication has serious side effects and requires regular monitoring by your physician. When taken to relieve the symptoms of DH, Dapsone should be taken in the smallest effective doses for as short a time as possible. Medications for DH should not be used during pregnancy.
Questions to Ask Your Doctor:
Should I take medication for this disease?
Excellent, if you stay on the gluten-free diet. The severity and frequency of eruptions will decrease as you continue with the diet. Iodine can trigger eruptions in some people. However, iodine is an essential nutrient and should not be removed from the diet without a physician's supervision.
Thyroid disease is most commonly associated with DH. Other autoimmune disorders that people with CD are at greater risk to develop include Addison' s disease, autoimmune chronic active hepatitis, Alopecia Areata, Graves' disease, insulin-dependent diabetes mellitus (type 1), myasthenia gravis, scleroderma, Sjogren's syndrome, systemic lupus erythematosus, and thyroid disease. This is not a complete list. Thyroid diseases and diabetes are the two most commonly associated diseases. It is not uncommon to have other skin conditions as well.