Clin Path 7: WBC Terminology and Neutrophil Physiology Flashcards
Identify the leukocyte morphology in this image
Explain medullary hematopoiesis from a blood stem cell into the different types of differentiated cells
blood stem cell to myeloid stem cell and lymphoid stem cell
myeloid stem cell to RBC, platelets, and myeloblasts
myeloblasts differentiate into WBC
lymphoid stem cell differentiates into lymphoblast which differentiates into a WBC
Name
Decrease in WBC
Increase in WBC
leukocytosis
leukopenia
Name
Decrease in lymphocytes
Increase in lymphocytes
lymphocytosis
lymphopenia
Name
Decrease in monocytes
Increase in monocytes
monocytosis
monocytopenia
Name
Decrease in neutrophils
Increase in neutrophils
neutrophilia
neutropenia
Name
Decrease in eosinophils
Increase in eosinophils
eosinophilia
eosinopenia
Name
Decrease in basophils
Increase in basophils
basophilia
basopenia
A dog has an increased leukocyte count due to an elevation in neutrophils and monocytes, but a decrease in lymphocytes. Use the correct terminology to describe the leukocyte abnormalities.
leukocytosis due to neutrophilia and monocytosis
with a concurrent lymphopenia
A cow has a decreased leukocyte count due to low numbers of neutrophils and lymphocytes. Use the correct terminology to describe the leukocyte abnormalities.
leukopenia due to neutropenia and lymphopenia
A cat has an increased leukocyte count due to increased numbers of lymphocytes, eosinophils, and basophils. Use the correct terminology to describe the leukocyte abnormalities.
leukocytosis due to lymphocytosis, eosinophilia, and basophilia
A dog has a normal leukocyte count with an increase in segmented neutrophils and band neutrophils but a decrease in lymphocytes, and eosinophils. Use the correct terminology to describe the leukocyte abnormalities.
Neutrophilia with a left shift, lymphopenia and eosinopenia
What is the WBC number in uL that is given from an analyzer?
10,000
Which should be used to interpret WBC count - relative or absolute?
absolute
If the relative differential count (%) of neutrophils is 60%, what is the absolute differential count?
60,000
If the relative differential count (%) of lymphocytes is 30%, what is the absolute differential count?
30,000
If the relative differential count (%) of eosinophils is 10%, what is the absolute differential count?
10,000
Why is it necessary to calculate a cWBC?
WBC impedance count counts nRBC toward WBC due to the analyzer seeing the nucleus
Which do you need to find a cWBC for - impedance count or optical count?
impedance
What is the cWBC equation?
WBC * 100/100+nRBC
In what case would you not need to find a cWBC?
if nRBC are WNL (<1-5)
Find the absolute WBC counts
Explain the basic sequence of neutrophil kinetics and the lengths of times associated with each
bone marrow (5 days) –> blood (10-12 hrs) –> tissue (<2 days)
Which cells are associated with the proliferating bone marrow?
myeloblasts
promyeloblasts
myelocyte
Which cells are associated with the maturation of bone marrow?
metamyelocytes
band
segmented
In the blood, explain circulating vs marginal cells
circulating are free floating in the blood vs marginal are adhered to endothelial cells by selectins
When pulling blood which cells will be sampled, circulating or marginal?
circulating
Explain the storage pool species differences
dogs and cats have a 1-2 day storage whereas cattle and horses have a small storage pool
Which species has more segmented neutrophils?
cats and dogs
Explain the maturation from myeloblast to segmented neutrophils. Which is more abundant?
myeloblast
promyelocyte
neutrophilic myelocyte
neutrophilic metamyelocyte
band neutrophil
segmented neutrophil
more segmented neutrophils
In a perfect world, which should be more abundant segmented or banded neutrophils?
What is an increase in band neutrophils indicative of?
inflammation!
Explain a degenerative left shift
there is an increase in band neutrophils and a decrease in neutrophils leading to a neutropenia
In which species is a degenerative left shift ominous in? Which species is it less concerning?
cats and dogs = ominous
horses = less concerning
Explain a regenerative left shift
neutrophilia
band neutrophils increase as does neutrophils but neutrophils exceed band
Explain a deep left shift
circulating metamyelocytes due to a demand to produce leukocytes due to inflammation
Explain the CBC findings of a regenerative left shift
a mild to moderate left shift accompanying a neutrophilia
What is the significance of a regenerative left shift?
the bone marrow is responding to tissue inflammation and releasing earlier neutrophils from the maturation pool (ie the band neutrophils)
Explain the CBC findings of a degenerative left shift
immature neutrophils > mature segmented neutrophils
What is the significance of a degenerative left shift?
bone marrow cannot keep up with the peripheral demand for neutrophils and is interpreted as overwhelming inflammation and often suggests poor prognosis
What are toxic neutrophils and what does it lead to?
inflammation
What is diffuse cytoplasmic basophilia due to? In which species can a mild form of it be normal in?
due to greater amount of RNA
normal in cats
What are dohle bodies? What species is 1-2 normal in?
blue grey, amorphous or angular cytoplasmic inclusions, reflects stacks of retained endoplasmic reticulum
Normal in cats
What is toxic vacuolization?
indistinct or frothy cytoplasmic vacuoles due to dispersed organelles
What is toxic granulation?
dust-like purple to dark pink cytoplasmic granules
What is a donut-shaped nucleus?
rarely noted - nucleus is round with a hole in the middle
What is a giant neutrophil?
rarely noted - neutrophil is larger than normal
Explain severity of toxicity from minimal to marked
minimal to mild - 1 or 2 of the most common morphologic features
moderate - usually 2 of the 3 most common morphologic features
marked - all 3 of the common features and/or toxic granulation
What are the 3 most common morphologic features of toxicity?
Cytoplasmic basophilia - 1st
Dohle body
vacuolization
What are 3 neutrophil infectious agents you may see on a blood smear
anaplasma phagocytophilum
ehrlichia spp
distemper inclusion
