From the Oregon State University study, the anemia of iron deficiency is usually characterized as microcytic and hyperchromatic, i.e., red blood cells are measurably smaller than normal and their hemoglobin content is decreased such that they are more pale than normal. I was under the impression that red blood cell width increased in iron deficiency. What am I missing or confusing here?

Dr. Amy Nett:  Yeah. So I think you’re talking about RDW. So the RDW increases in iron deficiency, but RDW actually stands for the red cell distribution width. So I think that might be what you’re confusing because you say the red blood cell width, but this is red cell distribution width. So the RDW is a measure of the variability in the size of the red blood cells. The MCV is the marker of red blood cell size or volume. So in iron deficiency, the size of the red blood cells decreases, which is indicated by a decreased or lower than normal MCV. But the RDW increases, meaning that there’s more variability in the size of the red blood cell. So hopefully that clarifies.