Pernicious anemia

Pernicious anemia is an autoimmune hematologic disorder characterized by the impaired intestinal absorption of dietary vitamin B12 (cobalamin), leading to megaloblastic anemia Primarily affecting older adults and individuals with autoimmune predispositions, the condition arises from autoimmune gastritis marked by autoantibodies against gastric parietal cells and intrinsic factor The resulting destruction of parietal cells causes intrinsic factor deficiency and achlorhydria, preventing the format...

Pernicious anemia is an autoimmune hematologic disorder characterized by the impaired intestinal absorption of dietary vitamin B12 (cobalamin), leading to megaloblastic anemia

Primarily affecting older adults and individuals with autoimmune predispositions, the condition arises from autoimmune gastritis marked by autoantibodies against gastric parietal cells and intrinsic factor Clinical and pathophysiologic hallmarks include defective erythroid DNA synthesis leading to macrocytic anemia, systemic manifestations of fatigue and glossitis, and potentially irreversible neurological sequelae such as peripheral neuropathy and subacute combined degeneration of the spinal co...

The resulting destruction of parietal cells causes intrinsic factor deficiency and achlorhydria, preventing the formation of intrinsic factor-cobalamin complexes required for ileal uptake

Clinical and pathophysiologic hallmarks include defective erythroid DNA synthesis leading to macrocytic anemia, systemic manifestations of fatigue and glossitis, and potentially irreversible neurological sequelae such as peripheral neuropathy and subacute combined degeneration of the spinal cord