<unk>  under low power. H&E stain. Autoimmune metaplastic<unk>  (AMAG) is an inherited form of<unk>  characterized by an immune response directed toward parietal cells and intrinsic factor. The presence of serum antibodies to parietal cells and to intrinsic factor are characteristic findings. The autoimmune response subsequently leads to the destruction of parietal cells, which leads to profound Achlorhydria (and elevated gastrin levels). The inadequate production of intrinsic factor also leads to vitamin B12 malabsorption and pernicious anemia. AMAG is typically confined to the gastric body and fundus. Achlorhydria induces G cell (gastrin-producing) hyperplasia, which leads to hypergastrinemia. Gastrin exerts<unk>  effect on enterochromaffin-like cells (ECL cells are responsible for histamine secretion) and is hypothesized to be one mechanism to explain the malignant transformation of ECL cells into carcinoid tumors in AMAG.
Atrophic gastritis
Lymphocytic esophagitis
Herpes esophagitis
Tropical ulcer
Gastric lymphoma
Eosinophilic esophagitis
Barrett's esophagus
Cytomegalovirus esophagitis