Celiac sprue: An immune disorder whereby the small intestine is injured when exposed to gluten, a protein found in wheat and related grains. Celiac sprue causes impaired absorption and digestion of nutrients through the small intestine. Symptoms include frequent diarrhea and weight loss. A skin condition called dermatitis herpetiformis is sometimes associated. The most accurate test for celiac sprue is a biopsy of the small bowel. Treatment involves avoidance of gluten in the diet. Medications are used for refractory (stubborn) sprue. Also known as gluten enteropathy.