Coeliac disease

Coeliac disease is an autoimmune disease triggered by gluten.

Gluten is a protein found in grains, such as wheat, barley, and rye. Gluten crosslinks starch fibers and gives dough its elasticity and chewiness. In genetically predisposed individuals, gluten is recognized as an antigen and triggers an immune response. Lymphocytes migrate into the epithelium of the small intestine and initiate an inflammatory reaction. If the person continues to consume gluten, the intestine remains chronically inflamed. This leads to shrinking of the villi and a decrease in the surface area of the small intestine.

Patients suffer from chronic constipation, diarrhoea, anaemia, fatigue, and children fail to thrive. The damage induced to the intestinal lining remains for a long time and the only effective treatment is a gluten-free diet. Gluten intolerance remains undiagnosed in most patients, therefore it is unknown how many people are affected by it. Recent studies estimate around 1 % of the population of Western countries suffers from coeliac disease.

Left panel shows 2 healthy orange villi with pink layer of epithelial cells lining them. A cellular lined circular structure inside the villi is empty. Next panel shows black dots representing lymphocytes infiltrating the orange part of the villi and the circular structure at the bottom which is labelled the crypt of lieberkuhn. Third panel shows the villi getting shorter and more lymphocytes. The last panel shows a lack of villi almost totally with the surface area of the small intestine being decreased and many lymphocytes in the red inflammed base.

Figure 1: Progression of chronic inflammation of the small intestine: (0) Healthy villi, (1) Antigens trigger Lymphocyte infiltration, (2) Lymphocytes accelerate immune response, (3) the villi shrink, (4) the surface of the small intestine is decreased.