Gluten is one of the two substances in our food that, on contact with the intestinal wall (a mucous membrane), can cause inflammation to spread over several square feet of intestinal surface. It is the gluey protein substance, especially in wheat and rye, that causes dough to be sticky. The other muco-toxin is lactose (milk sugar).
Many of these patients are being treated for IBS (irritable bowel syndrome) with drugs that help relax the irritated, spastic gut wall. Others are taking arthritis medicine for the joint pains. My preference would be to treat the cause, not the symptoms.
Many of the tests I use to find causes of chronic illness are done at specialized laboratories in larger cities. Most of these labs and tests are used by those of us who specialize in finding imbalances before they become a crisis.