macrocyte

cell

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Last updated

June 30, 2026

Quick Summary

A macrocyte is an exceptionally large red blood cell. The presence of macrocytes in the blood is known as macrocytosis. This condition typically occurs in anemias, which are characterized by a reduced amount of hemoglobin in the blood, impairing its oxygen-carrying capacity.123

Macrocytic anemia specifically refers to anemia where the average size of circulating red blood cells is larger than normal. This can result from impaired red blood cell production, often due to deficiencies in vitamin B12 or folic acid.3

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pernicious anemia
Pathophysiology
…large red blood cells called macrocytes; they reach the circulation but function abnormally. A deficiency of white blood cells (leukopenia) and platelets (thrombocytopenia) in the blood may occur.
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…large red blood cells called macrocytes; they reach the circulation but function abnormally. A deficiency of white blood cells (leukopenia) and platelets (thrombocytopenia) in the blood may occur.
Read More