How is dermatitis herpetiformis (DH) diagnosed?

DH is diagnosed by a skin biopsy, which involves removing a tiny piece of skin near the rash and testing it for the IgA antibody. DH is treated with a gluten-free diet and medication to control the rash, such as Dapsone or Sulfapyridine. Drug treatment is short term, usually until the gluten-free diet begins to relieve symptoms. It’s not necessary to perform an intestinal biopsy to establish the diagnosis of celiac disease in a patient with DH; the skin biopsy is definitive.