A high RDW indicates what type of abnormality in red blood cells?

A high red cell distribution width (RDW) indicates a wide range of red blood cell (RBC) sizes, which reflects greater variability in the volume of RBCs present in the blood. This variability can result from several factors, including the presence of different underlying conditions such as iron deficiency anemia or mixed anemia, where the bone marrow produces RBCs of varying sizes due to differing etiologies.

A wide RDW suggests that there is significant anisocytosis, which is the medical term for a variation in the size of RBCs. This can happen when the body is responding to anemia or when it is producing red blood cells at different stages of maturation, leading to a mix of small and large cells. This is particularly useful in diagnosing certain types of anemia, as it can help differentiate between cases caused by dietary deficiencies, chronic diseases, or bone marrow disorders.

In contrast, a narrow range of RBC sizes would be indicated by a low RDW, suggesting that the red blood cells are relatively uniform in size, which is typical of a normal or healthy state. An increase in RBC production or a decrease in overall RBC count wouldn't specifically relate to the RDW, as these metrics do not directly reflect size variations. Thus, the chosen answer clearly captures the