The size of the red blood cells is measured by ?
Ans. is 'a' i.e., MCV Mean cell volume (MCV) o The average volume of red blood cell in cubic micrometer. Normal value is 82-96 m3. MCV will be decreased in microcytic anemia, and will be increased in macrocytic (megaloblastic anemia). Mean cell hemoglobin (MCH1 o The average content of hemoglobin per red blood cell in picograms. Normal value is 27-33 pg. o MCH will be decreased in hypochromic (microcytic hypochromic anemia), and will be increased in megaloblastic anemia. Mean cell hemoglobin concentration (MCHC) o The average concentration of hemoglobin in a given volume of packed red blood cells, expressed in grams per deciliter. Normal value is 33-37 gm/dl. MCHC is increased in hereditary spherocytosis, not because of increased hemoglobin, but due to decerase volume of spherocytes. Red blood cell distribution width (RDW) o The cofficient of variation of red blood cell volume, i.e. degree of anisocytosis (abnormal variation in size of RBCs). Normal value is 11.5 - 14.5. Hematocrit or Packed cell volume (PCV1 The propoion of blood volume that is occupied by red blood cells. Normal values are about 45% for men and about 42% for women. o A decrease in the number or size of red cells also decreases the amount of space they occupy, resulting in lower hematocrit. Similarly an increase in the number or size of red cells increases hematocrit. Exceptions are thalassemia which can cause an increased number of red blood cells but a decreased size and hematocrit, and megaloblastic anemia which causes increase in size of red cells with decreased hematocrit. Reticulocyte count ---->quantitative measure of the bone marrow's production of new red blood cells. Reticulocyte count is increased in anemia due to blood loss or anemia in which there is no defect in RBC production --> It is a responce to componsate anemia. o Reticulocyte count is decreased when there is anemia which has defect in RBC production, e.g. macrocytic (Vit B 12, folic acid deficiency) anemia, microcytic (iron def. anemia), Aplastic anemia.
MCV
MCHC
ESR
MCH