hematology lab exam 2


immature RBC stages are confined to the bone marrow prior to reachong maturity except for _______ stage.

cytoplasmic RNA and ribosomes

reticulocytes are distinguished from fully mature erythrocytes their remaining

released into the blood stream where it takes them more than a day to become erythrocytes.

the reticulocyte spend two day maturing in the bone marrow and then where do they go?


1% of total circulating RBC populations are

because it shows the amount of effective RBC production (underproduction= hypoplastic BM; overproduction= hyperplasic BM).

why is the reticulocyte count significant

Defective erythropoiesis

persistently low reticulocyte counts, accompanied by anemia usually indicates:

chronic hemolytic anemia

persistently elevated reticulocyte counts usually indicate:

bone marrow failure

a drop in the erythrocyte counts to a very low value usuLly indicate


adult reference range for reticulocytes is:

1.7-7.0% (for ages 0-1 day)

newborn reference range for reticulocyte

supravital stains (new methyl blue -preferred- or brilliant cresyl blue)

what kind of stain needs to be used to differentiate reticulocytes from erythrocytes?


refractile bodies are not ______


is this a reticulocyte?

no (inclusion/refractile bodies)

is this a reticulocyte?

1:1 (3 drops of each)

what is the ratio of stain to blood in a reticulocyte count?

15 minutes but not longer than 30
then remix sample before making blood smears

how long must the blood/stain mixture be allowed to sit before making smears for a reticulocyte count?

count all reticulocytes in square A (include those in square B), count all erythrocytes in square B
continue until you reach a total of 112 erythrocytes

how do you count using a miller disk?

reticulocyte % = (total # of reticulocytes counted x 100) / (total # of erythrocytes counted x 9)
before reporting, do two counts total and make sure the reticulocyte % agree within +/- 10%.

how do you calculate the reticulocyte count with a miller disk?

very low hematocrits or very high hematocrits
less stain for low and more stain for high

the ratio of stain to blood should be changed for blood samples having what conditions?

anemic patients (to reflect the total production of red cells irrespective of the # of red cells present)

what kind of patients require a corrected reticulocyte count?

corrected reticulocyte count % = (patient hematocrit � reticulocyte count %) / (avg normal hematocrit of 45%)

how to calculate a corrected reticulocyte count:

heinz bodies and howell jolly bodies

which two cell inclusions must you look our for when ID-ing reticulocytes?

find a field with a single layer of cells
using one tally count all the reticulocytes in the field
using another tally counter, count all the erythrocytes (including reticulocytes) in the field
move to anotjer field and repeat until you reach 1000 erythro

STEPS to calculate a reticulocyte count without a miller disk:

reticulocyte % = (total # of reticulocytes counted �100) / (total # of erythrocytes counted)

formula for calculating a reticulocyte count without a miller disk:

use the absolute reticulocyte count

how do you calculate the total number of reticulocytes in 1 liter of blood?

abs reticulocyte count = (reticulocytes % � RBC count � 10^12/L) / 100

how do you calculate the absolute reticulocyte count?

differential white cell count

enumeration of the different types of white blood cells found in blood


how many wbc are counted in a differential white cell count?

differential white cell count

the differential count is another name for

last (erythrocyte morphology and platelet estimates are done prior)

the differential is the ______ step in the examination of a blood smear


5 types of whc that may be normally present in the blood

bone marrow

where do wbc develop?


production of white blood cells


for differentials and cell counting, slide should be examined using the ____ pattern

Wright's stain

what type of stain should be used for a differential wbc count

Nucleated Red Blood Cell

a red blood cell that contains a nucleus. It resembles a white blood cell under low-power magnification; important to note (because they are considered abnormal findings in adults) but not to be counted on a differential count.

Smudge cells (large number indicate increased cellular fragility)

cell that show up in large numbers in patients who have Chronic Lymphocytic Leukemia (CLL)

segmented neutrophils 40-80
band neutrophils 0-5
eosinophils 0-5
basophils 0-2
lyphocytes 25-35
monocytes 2-10

reference ranges for normal wbc

outline for studying stained blood smears

acute infection and inflammatory changes

increased number of leukocytes associated with


cells whose basic contents attract the acid ions of the stain making then a reddish orange color

allergies, skin disease, and parasitic infections

increased eosinophils associated with


the cell that attracts the basic dye in the stain (making them a deep purple/blue color

humoral immunity and cell-mediated immunity

lymphocytes provide both _____ immunity and _______ immunity


largest of the peripheral blood cells

WBC and no RBC

body fluids normally contain few if any ______ and no ______.