An increased RDW on an electronic cell counter is correlated with which condition?

An increased Red Cell Distribution Width (RDW) indicates a greater variation in the size of red blood cells (RBCs), which is a hallmark of anisocytosis. Anisocytosis refers to the presence of red blood cells that are unequal in size, often associated with various conditions that disrupt normal erythropoiesis or indicate an underlying disease process.

When measuring RDW, a higher value signifies a larger difference in cell size, which can suggest nutritional deficiencies such as iron, vitamin B12, or folate deficiency, as well as bone marrow disorders or hemolytic anemia. In these cases, the variation in red blood cell size reflects the body’s response to stressors affecting RBC production or lifespan.

Understanding RDW in relation to anisocytosis is crucial, as it helps diagnose conditions that lead to disparities in RBC sizes, allowing clinicians to target further diagnostic tests or treatment options based on the underlying cause.