Autoimmune chronic atrophic gastritis can lead to which of the following?

Autoimmune chronic atrophic gastritis occurs when the body's immune system attacks the gastric mucosa, leading to chronic inflammation and the eventual destruction of gastric glandular cells. One significant consequence of this condition is the loss of parietal cells, which produce intrinsic factor. Intrinsic factor is crucial for the absorption of vitamin B12 in the intestines.

When there is insufficient intrinsic factor due to the destruction of parietal cells, vitamin B12 malabsorption occurs, ultimately leading to pernicious anemia. This type of anemia is characterized by the production of large, immature red blood cells and is a direct result of vitamin B12 deficiency.

This relationship explains why autoimmune chronic atrophic gastritis is closely associated with pernicious anemia. The other conditions mentioned do not directly result from the loss of parietal cells or intrinsic factor deficiency, which is central to the pathophysiology of pernicious anemia.