Red blood cell distribution width volume (MCV) results to determine the possible causes of the anemia. It is mainly used to differentiate an anemia of mixed causes from an anemia of a single cause. Deficiencies of Vitamin B or folate produce a macrocytic anemia (large cell anemia) in which the RDW is elevated in roughly two-thirds of all cases. However, a varied size distribution of red blood cells is a hallmark of iron deficiency anemia, and as such shows an increased RDW in virtually all cases. In the case of both iron and B deficiencies, there will normally be a mix of both large cells
Hematopoietic stem cell Hematopoietic stem cell Hematopoietic stem cells (HSCs) are the stem cells that give rise to other blood cells. This process is called haematopoiesis.<ref name="Birbrair n/a–n/a"></ref> This process occurs in the red bone marrow, in the core of most bones. In embryonic development, the red bone marrow is derived from the layer of the embryo called the mesoderm. Hematopoiesis is the process by which all mature blood cells are produced. It must balance enormous production needs (the average person produces more than 500 billion blood cells every day) with the need to precisely regulate the number of each blood cell type