Celiac disease, or celiac sprue, is a chronic disorder of the small intestine caused by sensitivity to gluten, a protein found in wheat and rye and, to a lesser extent, in oats and barley.

It causes poor absorption by the intestine of fat, protein, carbohydrates, iron, water, and vitamins A, D, E, and K.

The word sprue derives from the Dutch spruw, which means mouth blisters. These were described as an important sign of the illness by the Dutch physician Vincent Ketelaer in 1669, almost three...