Microcytic anemia (BrE: anaemia) is a generic term for any type of anemia characterized by small red blood cells. The normal mean corpuscular volume (abbreviated to MCV on full blood count results) is 76-100 fL, with smaller cells (<76 fL) described as microcytic and larger cells (>100 fL) as macrocytic.
In microcytic anemia, the red blood cells (erythrocytes) are usually also hypochromic, meaning that the red blood cells are paler than usual. This can be quantified as the mean corpuscular hemoglobin or mean cell hemoglobin (MCH), the amount of hemoglobin per cell; the normal value is 27-32 picograms (pg). Similar is the mean corpuscular hemoglobin concentration (MCHC), giving the amount of hemoglobin per volume of erythrocytes (normally about 320-360 g/L or 32-36 g/dL). Typically, therefore, anemia of this category is described as "microcytic, hypochromic anemia".
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