Most doctors assume that celiac desease is rare among Asians, but the celiac genes, DQ2 and DQ8, are not that uncommon in the Taiwanese population and in other Asian populations. Celiac disease is a hereditary intolerance to gluten, a protein found in wheat, barley and rye. It is a serious disease that can lead to autoimmune disorders and cancer. Celiac disease is associated with diabetes, thyroid disease, autoimmune liver disease, cardiomyopathy, rheumatoid arthritis, Addison's disease, osteoporosis, peripheral neuropathy, migraines, depression, and infertility. Patients with celiac disease are at high-risk for thyroid cancer, adenocarcinoma of the small intestine, lymphoma, esophageal cancer, melanoma, and malignancy in childhood. Strict avoidance of gluten is the only way to treat celiac disease.
Excerpts from Wikipedia.org
Coeliac disease, also spelled celiac disease, is an autoimmune disorder of the small bowel that occurs in genetically predisposed people of all ages from middle infancy. Symptoms include chronic diarrhoea, failure to thrive (in children) and fatigue, but these may be absent and symptoms in all other organ systems have been described. It is estimated to affect about 1% of Indo-European populations, although significantly underdiagnosed. A growing portion of diagnoses are being made in asymptomatic persons as a result of increasing screening.
Coeliac disease is caused by a reaction to gliadin, a gluten protein found in wheat (and similar proteins of the tribe Triticeae which includes other cultivars such as barley and rye). Upon exposure to gliadin, the enzyme tissue transglutaminase modifies the protein, and the immune system cross-reacts with the bowel tissue, causing an inflammatory reaction. That leads to flattening of the lining of the small intestine, which interferes with the absorption of nutrients. The only effective treatment is a lifelong gluten-free diet.
Role of Other Grains
Wheat varieties or subspecies containing gluten such as spelt and Kamut®, and the rye/wheat hybrid triticale, also trigger symptoms.
Barley and rye also induce symptoms of coeliac disease. A small minority of coeliac patients also react to oats. It is most probable that oats produce symptoms due to cross contamination with other grains in the fields or in the distribution channels. Other cereals, such as maize (corn), quinoa, millet, sorghum, rice are safe for a patient to consume. Other carbohydrate-rich foods such as potatoes and bananas do not contain gluten and do not trigger symptoms.
Signs and Symptoms
Classic symptoms of coeliac disease include diarrhoea, weight loss (or stunted growth in children), and fatigue, but while coeliac disease is primarily a bowel disease, bowel symptoms may also be limited or even absent. Some patients are diagnosed with symptoms related to the decreased absorption of nutrients or with various symptoms which, although statistically linked, have no clear relationship with the malfunctioning bowel. Given this wide range of possible symptoms, the classic triad is no longer a requirement for diagnosis.
Children between 9 and 24 months tend to present with bowel symptoms and growth problems shortly after first exposure to gluten-containing products. Older children may have more malabsorption-related problems and psychosocial problems, while adults generally have malabsorptive problems. Many adults with subtle disease only have fatigue or anaemia.
Coeliac disease has been linked with a number of conditions. In many cases it is unclear whether the gluten-induced bowel disease is a causative factor or whether these conditions share a common predisposition.
- IgA deficiency is present in 2% of patients with coeliac disease, and in turn this condition features a tenfold increased risk of coeliac disease. Other features of this condition are an increased risk of infections and autoimmune disease.
- Dermatitis herpetiformis; this itchy cutaneous condition has been linked to a transglutaminase enzyme in the skin, features small bowel changes identical to those in coeliac disease and occurs more often (in 2%) in patients with coeliac disease.
- Neurological associations: epilepsy, ataxia (coordination problems), myelopathy, peripheral neuropathy and schizophrenia have all been linked with coeliac disease, but the strength of these associations and the causality are still subject to debate.
- Growth failure and/or pubertal delay in later childhood can occur even without obvious bowel symptoms or severe malnutrition. Evaluation of growth failure often includes coeliac screening.
- Miscarriage and infertility.
- Hyposplenism (a small and underactive spleen) - it is unclear whether this actually increases infection risk in the same way as in other people without a functioning spleen.
- Other auto-immune disorders: diabetes mellitus type 1, autoimmune thyroiditis, primary biliary cirrhosis and microscopic colitis.
Antibody Testing
Four serological blood tests exist for coeliac disease. The most widely used ones detect an antibody of the IgA type against particular antigens in the small bowel. Older tests detected antibodies against reticulin (ARA) or gliadin (AGA), but recent evidence supports the use of the more modern tests, namely those detecting IgA antibodies against endomysium (EMA) or tissue transglutaminase (TTG). Generally, serology may be unreliable in young children, with anti-gliadin performing somewhat better than other tests in children under five.
Guidelines recommend that a total serum IgA level is checked in parallel, as coeliac patients with IgA deficiency may be unable to produce the antibodies on which these tests depend ("false negative"). In those patients, IgG antibodies against transglutaminase (IgG-TTG) may be diagnostic.
HLA Genetic Typing
Antibody testing and HLA testing have similar accuracies.
Endoscopy
An upper endoscopy with biopsy of the duodenum (beyond the duodenal bulb) or jejunum is performed. It is important for the physician to obtain multiple samples (four to eight) from the duodenum. Not all areas may be equally affected; if biopsies are taken from healthy bowel, it would result in false negative results.
Most patients with coeliac disease have a small bowel that appears normal on endoscopy; however, five endoscopic findings have been associated with a high specificity for coeliac disease when all are found: scalloping of the small bowel folds (pictured), paucity in the folds, a mosaic pattern to the mucosa (described as a cracked-mud appearance), prominence of the submucosal blood vessels and a nodular pattern to the mucosa.
Until the 1970s, biopsies were obtained using metal capsules attached to a suction device. The capsule was swallowed and allowed to pass into the small intestine. After X-ray verification of its position, suction was applied to collect part of the intestinal wall inside the capsule. One much utilized capsule system is the Watson capsule. This method has now been largely replaced by fiberoptic endoscopy, which carries a higher sensitivity rate and a lower error frequency.