A Light and Electron Microscopic Study of Sigmoid Colonic Mucosa in Adult Celiac Disease

Sigmoidoscopic and light microscopic examinations of sigmoid colonic mucosa of four untreated and two treated patients with adult celiac disease were normal. Electron microscopic examination of this mucosa obtained from the four untreated patients revealed abnormalities of the microvilli and collections of finely granular material, similar to apical cytoplasm, within the microvillous borders of principal cells and in the lumens of crypts. This material appeared to be exuded from microvilli. No ultrastructurul abnormalities were observed in the mucosa obtained from the patients after successful treatment with a gluten-free diet. Gliadin peptides, obtained by digestion with pepsin and trypsin, produced minimal microvillous changes when given as an enema to one patient who had been treated with a glutcn-free diet.