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 an autoimmune gluten intolerance disease linked with celiac disease. 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.