Autoimmune gastritis is associated with deficiency of vitamin?
High-Yield Explanation
Ans. is 'b' i.e., B12 * In autoimmune gastritis, two important auto antibodies causing damage are anti-parietal cell antibodies (most common) and antibodies against intrinsic factor; anti-IF (most specific). Anti-parietal cell antibodies are directed against proton pump (H+ K+ ATPase). The effect of these antibodies are: -a) Achlorhydria : Due to loss of parietal cells.b) Vitamin B-12 deficiency and pernicious anemia : Due to deficiency of IF cells (secreted by parietal cells) as well as damage of IF by anti-IF antibodies.c) Antral endocrine cell hyperplasia (G-cell hyperplasia) : Due to achlorhydria (normally gastric acid has inhibitory effect on G-cells).d) Reduced serum pepsinogen I: Only pepsinogen I is reduced (pesinogen II is normal)