Dermatitis herpetiformis is related to celiac disease because both conditions are caused by gluten intolerance. Dermatitis herpetiformis is a rash on the skin that is extremely itchy and appears with big red blisters. The rash is most often located on your elbows, knees, and behind. Those who suffer from the rash rarely have digestive symptoms.
If you were to have the rash biopsied, it would contain antibodies similar to those found in tissue from the small intestines of someone with celiac disease. In fact, dermatitis herpetiformis causes similar damage to that of celiac disease in the small intestine. Dermatitis herpetiformis is caused by intolerance to gluten and is treated with the same gluten-free diet that someone with celiac disease would be on.