Pernicious Anaemia/ Autoimmune gastritis

Autoimmune gastritis is a pathological lesion that may eventuate in the development of pernicious anaemia. Generally autoantibodies are found circulating against parietal cell H/K-ATPase which is the primary diagnostic marker for gastritis. H/K-ATPase is the most abundant membrane protein of the canicular and tubovesicular membranes of parietal cells and is responsible for the acidification of the stomach. Autoantibodies to intrinsic factor can also be detected.
Vitamin B₁₂ deficiencies are also indicative of this disease as autoantibodies to intrinsic factor inhibit the binding to vitamin B₁₂ complex thus stopping its uptake within the ileum.

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