Autoimmune Metaplastic Atrophic Gastritis

An autoimmune metaplastic atrophic gastritis (AMAG) is an inherited autoimmune disease that affects the parietal cells and leads to hypochlorhydria and decreased production of intrinsic factor. Following are atrophic gastritis, a vitamin B12 malabsorption and often pernicious anemia. The risk of a gastric adenocarcinoma is increased by 3 times. The diagnosis is made endoscopically. The treatment consists of parenteral administration of vitamin B12.

Patients with AMAG have antibodies against parietal cells and its components (including the intrinsic factor and the Protenenpumpe H +, K + -ATPase belong). AMAG is autosomal dominant. Some patients also develop Hashimoto’s thyroiditis and 50% have antibodies against thyroid tissue; conversely antibodies against parietal cells in 30% of patients are found with a thyroiditis.

An autoimmune metaplastic atrophic gastritis (AMAG) is an inherited autoimmune disease that affects the parietal cells and leads to hypochlorhydria and decreased production of intrinsic factor. Following are atrophic gastritis, a vitamin B12 malabsorption and often pernicious anemia. The risk of a gastric adenocarcinoma is increased by 3 times. The diagnosis is made endoscopically. The treatment consists of parenteral administration of vitamin B12. Patients with AMAG have antibodies against parietal cells and its components (including the intrinsic factor and the Protenenpumpe H +, K + -ATPase belong). AMAG is autosomal dominant. Some patients also develop Hashimoto’s thyroiditis and 50% have antibodies against thyroid tissue; conversely antibodies against parietal cells in 30% of patients are found with a thyroiditis. The lack of intrinsic factor leads to vitamin B12 deficiency and possibly the formation of a megaloblastic anemia (pernicious anemia, megaloblastic macrocytic anemia) and neurological symptoms (subacute combined degeneration, symptoms and complaints). A hypochlorhydria leads to the G-cell hyperplasia and increased Serumgastrinspiegeln (often> 1000 pg / ml). Increased gastrin lead to enterochromaffinähnlichen cell hyperplasia, which occasionally undergoes a transformation to a carcinoid. In some patients, AMAG may be associated with chronic Helicobacter pylori infection, although the relationship between the two diseases is not clear. A gastrectomy and chronic acid suppression with a proton pump inhibitor cause similar deficiencies of intrinsic factor secretion. In the areas with atrophic gastritis in the gastric body and -fundus to metaplastic changes can manifest. Patients with AMAG have a 3-fold increased risk of developing adenocarcinoma of the stomach. The diagnosis is made by an endoscopically obtained biopsy. Vitamin B12 levels in serum should be measured. Antibodies against parietal cells can be detected, the test is not done routinely. The problem of indication for surveillance endoscopy for cancer screening has not been resolved; Follow-up examinations are not necessary, unless in the initial biopsy are pathological histological findings (z. B. Dyplasie) to see and there are symptoms. No treatment other than the parenteral replacement of vitamin B12 is necessary.

Health Life Media Team

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