What is dermatitis herpetiformis?

Dermatitis herpetiformis (DH) is an extremely itchy, chronic skin rash with bumps and blisters typically found on the elbows, knees, back and buttocks.  The cause is unknown, however it is frequently linked to celiac disease.  The diagnosis of DH is confirmed with a simple blood test for IgA antibodies and a skin biopsy.  Treatment consists of medications and a gluten-free diet.