Macrocytosis

Excerpt

Macrocytosis refers to the finding of enlarged red blood cells. The measurement of RBC size is reported in the complete blood count as mean corpuscular volume (MCV). An elevated mean corpuscular hemoglobin accompanies most elevated MCV reports. The elevation of MCV and/or mean corpuscular hemoglobin suggests macrocytosis. In some cases, discovering macrocytosis may not necessitate further testing or treatment. However, practitioners should understand the importance of macrocytosis in the potential development of clinically significant anemia (macrocytic anemia), and they should understand the range of pathology that macrocytosis may signify, often implicating extra-hematologic organ systems. Close attention to historical, physical exam, and laboratory findings helps determine the underlying etiology, which, in turn, dictates management strategies for patients with macrocytosis.