RED BLOOD CELL INDICES Prepared by Yasser M

RED BLOOD CELL INDICES Prepared by: Yasser M. EL-dahdouh

RED BLOOD CELL INDICES They are also called red cell absolute values or erythrocyte indices. Red blood cell indices are measurements that describe the size and oxygen- carrying protein( hemoglobin) content of red blood cells. The indices are used to help in the differential diagnosis of anemia.

**The relationships between the hematocrit, the hemoglobin, and the red blood cells are converted to red blood cell indices through mathematical formulas. ** The indices include these measurements: 1 - Mean corpuscular volume ( MCV). 2 - Mean corpuscular hemoglobin ( MCH). 3 - Mean corpuscular hemoglobin concentration ( MCHC).

MCV “ MEAN CORPUSCULAR VOLUME “ ** is the average volume of the RBCs in femtoliters( fl ), or 10^-15 L. MCV = HCT(%) * 10/ RBCs count (10^-12/L ) ** Cells of normal size ( MCV is 80 – 100 fl )are called normocytic, Smaller cells are microcytic, Larger cells are macrocytic.

These size catedories are used to classify anemia. Normocytic anemia have normal size cells and a normal MCV. Microcytic anemia have small cells and a decreased MCV. Macrocytic anemia have large cells and a increased MCV. Example: Hct= 45%, RBCs count= 5. 0 * 10^12/L, MCV= 45 * 10 / 5. 0 = 90 fl.

MCH “ MEAN CORPUSCULAR HEMOGLOBIN” ** is the average weight of Hb in an RBC, expressed in the units of picograms ( pg) or ( 10^-12 g). MCH= Hb(g/dl) * 10 / RBCs count ( 10^12/L). ** Reference range ( 28 – 32 pg ). ** The MCH is not generally considered in the classification of anemia.

Example: Hb= 16 g/dl. RBCs connt= 5. 0 * 10^12/L. MCH= 16. 0 * 10 / 5. 0= 32. 0 pg

MCHC ** is the average concentration of Hb in each individual erythrocyte. ** The units used are gram per deciliter ( formerly referred to as a percentage ). MCHC= Hb(g/dl) * 100 / Hct (%) ** Reference range ( 32 – 37 g/dl ). * Hypo chromic cells are less than 32 g/dl. * Hyper chromic cells are greater than 37 g/dl. *Values of normo chromic cells range from 32 to 37 g/dl.

Anemia: a variety of condition in which a person blood can not carry as much oxygen as it should due to a decreased number or size of red blood cells. Hypochromic: a descriptive term applied to a red blood cell with a decreased concentration of Hb. Hyperchromic: a descriptive term applied to a red blood cell with a increased concentration of Hb.