What condition develops due to the formation of autoantibodies against parietal cells and intrinsic factor?

The condition that develops due to the formation of autoantibodies against parietal cells and intrinsic factor is pernicious anemia. This autoimmune disorder is characterized by the destruction of gastric parietal cells, which produce intrinsic factor—a protein essential for the absorption of vitamin B12 in the intestines.

When intrinsic factor is not available due to the autoimmune attack on parietal cells, the body is unable to properly absorb vitamin B12. Over time, this deficiency leads to megaloblastic anemia, neurological defects, and various other complications associated with vitamin B12 deficiency.

Understanding pernicious anemia is crucial because it highlights the immune-mediated mechanisms that can lead to significant clinical consequences. Chronic atrophic gastritis, while also related to autoimmune processes involving parietal cells, does not directly emphasize the role of intrinsic factor deficiency as pernicious anemia does. Pseudomembranous colitis, on the other hand, is an entirely different condition usually associated with antibiotic use and Clostridium difficile infection, and iron deficiency anemia is typically related to dietary deficiencies or chronic blood loss rather than autoimmune processes targeting intrinsic factor. Thus, pernicious anemia is the most accurate answer as it directly links the autoimmune response to specific clinical outcomes.