Common symptoms of a gluten intolerance include diarrhea, cramping, bloating, gas, constipation, and anemia. Celiac disease, which is due to gluten intolerance and is an autoimmune disease, has many of the same symptoms. A unique rash called dermatitis herpetiformis affects 15% to 25% of people with celiac disease. The intensely itchy rash may show up on your elbows, knees, and buttocks. If you have these symptoms, talk to your doctor.