Pernicious anemia is a severe chronic anemia caused by deficiency of vitamin B12 and impaired absorption due to gastric secretions. Which condition is this?

Pernicious anemia is a severe chronic anemia caused by deficiency of vitamin B12 and impaired absorption due to gastric secretions. Which condition is this?

• A. Pernicious anemia
• B. Iron-deficiency anemia
• C. Aplastic anemia
• D. Sickle cell anemia

Answer: (A)

This describes pernicious anemia, a severe chronic anemia caused by vitamin B12 deficiency due to impaired absorption from the stomach. Vitamin B12 absorption requires intrinsic factor, a protein produced by gastric parietal cells; when intrinsic factor is deficient or gastric secretions are impaired, B12 cannot be absorbed effectively, leading to pernicious anemia. The lack of B12 disrupts DNA synthesis in red blood cell precursors, causing megaloblastic (larger-than-normal) red cells and a high MCV, and it can also lead to neurological symptoms from impaired myelin production. This condition is distinct from iron-deficiency anemia (microcytic from iron shortfall), aplastic anemia (bone marrow failure with pancytopenia), and sickle cell anemia (a genetic hemoglobinopathy with misshapen cells).

This describes pernicious anemia, a severe chronic anemia caused by vitamin B12 deficiency due to impaired absorption from the stomach. Vitamin B12 absorption requires intrinsic factor, a protein produced by gastric parietal cells; when intrinsic factor is deficient or gastric secretions are impaired, B12 cannot be absorbed effectively, leading to pernicious anemia. The lack of B12 disrupts DNA synthesis in red blood cell precursors, causing megaloblastic (larger-than-normal) red cells and a high MCV, and it can also lead to neurological symptoms from impaired myelin production. This condition is distinct from iron-deficiency anemia (microcytic from iron shortfall), aplastic anemia (bone marrow failure with pancytopenia), and sickle cell anemia (a genetic hemoglobinopathy with misshapen cells).