Intestinal permeability and screening tests for coeliac disease.

Abstract

In coeliac disease, there is an increase in passive intestinal permeability to large polar molecules, ranging in size from proteins' down to oligosaccharides. In contrast, small polar molecules are malabsorbed. We have described34 our preliminary findings using a test of intestinal permeability (known as the cellobiose/mannitol test or 'sugar test' for short), based on the simultaneous oral administration and five-hour urinary recoveries of two probe molecules. The larger molecule used was cellobiose, a disaccharide (molecular radius 5A), and the smaller was mannitol, a polyhydric alcohol (molecular radius 4A). We showed that untreated coeliacs absorbed significantly more cellobiose, and less mannitol than control patients, and, when the result was expressed as a ratio (cellobiose recovery/ mannitol recovery), the discrimination was greatly enhanced. We postulated that, by expressing the result in this way, the sensitivity of the test as a screening procedure would be increased, and that, providing the two molecules were not too dissimilar

Abnormal Small Intestinal Permeability to Sugars in Patients with Crohn’s Disease of the Terminal Ileum and Colon

“…There was no evidence clinically or radiologically that any of our patients had proximal ileal or jejunal disease. However, Cobden et al [12] studied 7 patients with ileocolonic Crohn's disease using similar techniques, but found no per meability abnormalities, whereas of 8 pa tients with proximal small intestinal Crohn's disease, 5 had permeability abnormalities.…”

Nutrition in Celiac Disease

“…The examination of gut permeability is able to show the integrity of intestinal barrier [15]. In patients with untreated celiac disease is gut permeability increased, after gluten-free diet decreases in several months to basic value and its examination served (in time before good and valid serological markers) as screening test for celiac disease [16,17,18].…”

Pancreatic endocrine and exocrine changes in celiac disease

“…Earlier studies measuring xylose absorption were limited in ability to separate pancreatic and intestinal causes of steatorrhea, especially if the degree of impairment was mild [19] . Subsequent attempts to define altered intestinal permeability using large molecules (e.g., cellulobiose, mannitol) [20] or separate pancreatic insufficiency from intestinal dysfunction with noninvasive stable isotopes [21] have not become widely accepted. Severe structural changes have also been documented.…”