What is the hallmark of iron-deficiency anemia on a peripheral blood smear?

The hallmark of iron-deficiency anemia on a peripheral blood smear is the presence of microcytic and hypochromic red blood cells. This observation is significant because it reflects the body’s inability to produce hemoglobin adequately due to a lack of iron, which is essential for hemoglobin synthesis. As a result, the red blood cells that are produced are smaller than normal (microcytic) and contain less hemoglobin, making them paler (hypochromic).

In iron-deficiency anemia, the decrease in hemoglobin concentration leads to a reduced oxygen-carrying capacity of the blood, which is visible in the physical characteristics of the red blood cells under the microscope. The combination of microcytosis and hypochromia is a direct consequence of impaired hemoglobin production and is a classic finding that aids in the diagnosis of this condition.

Other descriptions of red blood cells would not typically be associated with iron-deficiency anemia. For example, high volume and hyperchromic red blood cells would indicate a different type of anemia, such as hereditary spherocytosis, while normocytic and normochromic cells could be indicative of a more chronic anemia or other underlying issues where red blood cell production may not be as severely impacted.