RBC indices reference - wintrobe , kawthalkar

1. Presented by – Dr. Pritika Nehra
Moderator – Dr. Vinod Mam

2.  Used for determining the size, content, and Hb
concentration of red cells .
 Useful in the morphologic characterization of
anemias.
 They may be calculated from the red cell count, Hb
concentration, and Hct.

3.  Mean cell volume (MCV)
 Mean cell hemoglobin (MCH)
 Mean cell hemoglobin concentration(MCHC)
 Red cell distribution width (RDW)

4.  average size of the red cells.
 measured directly by automated instruments
from the measurement of volume of each red
cell.
 With semiautomated instruments and by manual
method, it is obtained by
MCV = PCV in% × 10
Red cell count in million/cmm

5.  MCV is expressed in femtoliters or fl (10–15
of a liter).
 It corresponds with red cell diameter on blood
smear.
 Normal MCV is 80-100 fl.

7. Normal peripheral smear. Erythrocytes appear as circular,
homogeneous disks of nearly uniform size, ranging from 6 to 8 μm in
diameter, with central pallor not exceeding more than one third of the
cell. On average, the red cells are approximately the same size as the
nucleus of a small lymphocyte

8. Microcytic red cells in iron deficiency anemia. Red
cells are hypochromic—the amount of hemoglobin per
cell is decreased, and the central pale area becomes
larger

9. Macrocytes. Red cells are larger and thicker,
stain deeply, and lack central pallor

10. Dimorphic anemia.
Anisocytosis and anisochromia
characterized
by the presence of microcytic cells,
normocytic cells, and few macrocyte
characteristic of sideroblastic anemias
 also found some weeks after iron therapy for iron
deficiency anemia
in a hypochromic anemia after transfusion with
normal cells.

11.  Average amount of hemoglobin in a single red cell.
 MCH = Hemoglobin in grams/dl × 10
Red cell count in millions/cmm
 MCH is expressed in picograms or pg
 Reference range is 27-32 pg.
 Decreased in microcytic hypochromic anemia
 Increased in macrocytic anemia & in newborns

12.  concentration of hemoglobin in 1 dl or 1 liter of
packed red cells.
 expressed in grams/dl or grams/liter
 MCHC = Hemoglobin in grams/dl × 100
PCV in %
 Reference range is 30-35 grams/dl.

13.  MCHC corresponds with degree of
hemoglobinization of red cells on a blood smear
 If MCHC is normal, red cell is normochromic
 If low, red cell is hypochromic
 MCHC is raised in hereditary spherocytosis and
is decreased in hypochromic anemia

14. Hypochromic red cells
Red cells are hypochromic—the
amount of hemoglobin per cell is
decreased, and the central pale
area becomes larger
MCH is decreased
MCHC is decreased

15. Hereditary
spherocytosis
Spherocytes are nearly
perfectly round
in shape, smaller than normal
red cells, and lack central
pallor (hyperchromic)
MCH is normal
MCHC is usually increased because of a reduced
surface/volume ratio

17.  quantitative measure of the variation in red cell size
(anisocytosis)
 higher the value, the more heterogeneous the RBC
population size.
 Normal RDW is 11.0 to 14.5.
 increased in iron deficiency, and this often is useful
in distinguishing iron deficiency from thalassemia
trait conditions in which the RDW is normal