In a person who is suffering from celiac disease, mucosa of the small intestine negatively reacts to gluten, a protein found in wheat and other grains. Celiac disease rarely occurs for the first time in adulthood, but almost always in early childhood. Therefore, the disease is fully described in the part relating to children (see celiac disease article).
If celiac disease first appears in adulthood, symptoms include abdominal pain and swelling, diarrhea, weight loss, and general weakness. If you notice these symptoms, go to your doctor. Diagnosis and treatment of this disease are basically the same in adults and children.