WBC 1 Flashcards
why should you care about nucleated red blood cell counts when consideing a leukogram?
because these nucleted RBCs can get confused with WBCs on the machine
what are 3 considerations to remember when taking a blood sample and wanting to check for inflammation?
- we only see what is circulating in the blood and not what is happening in the tissues
- we only sample the center of the blood vessel (more of the circulating pool vs marginating pool)
- myelopoiesis takes time! white blood cells may be being made in the bone marrow but you may not be able to see them yet
during inflammation, is there usually more neutrophils in the circulating pool or the maringating pool?
the marginating pool usually has more, in dogs the ratio of marginating to circulating is usually 2 or 3:1
lymphocyte numbers in the body might be higher than the blood work shows. why?
because many lymphocytes circulate through lymphatics and lymph nodes so we dont see them in the blood
!why don’t the following terms exist:
- esoinophenia
- basopenia
- monocytopenia
because there is already a small amount expected in circulation, you can’t get less than 1 or zero
what are the 4 most common causes of a neutrophilia?
- physiologic (stress)
- steroids
- inflammatory
- could also be neoplastic but less common
what are two causes for an eosiniphilia? What is important to remember about eosinophils as to why there are usually so few of them?
- parasitism
- allergic/hypersensitivity
tissue eosiniphilia may not be reflected in the peripheral blood: eosinophils reside in tissues and parasites are usually in tissues, so you may not see many eosiniphils in the blood even though the animal may have a bad parasitic infection
what are two causes for a monocytosis?
- increased demand for phagocytic cells (inflammation, necrosis, granuloma, neoplasia, trauma)
- physiologic/steroid
(monocytic leukemia is rare but can happen)
what are two reasons why you may have a basophilia?
- parasitism
- allergies/hypersensitivity
what are 5 reasons why you might get a lymphocytosis?
- physiologic
- chronic antigenic stimulation (vaccine, chronic abscess, etc)
- the animal is young
- post vaccination
- lymphocytic leukemia
what are 3 reasons you may get a neutropenia?
- decreased production of neutrophils in bone marrow (chemo, estrogen, parvo, etc)
- cellular shift rom circulating to marginating (endotoxemia)
- increased tissue emigration outstripping bone marrow production (like with severe acute inflammation like pyothorax, all neutrohpils being dumped into the thorax)
what is the most common reason to get a lymphopenia?
- stress leukogram
- less commonly, leakage of chyle or immunodeficinecy
blood leukocyte concentrations are influenced by 3 factors which are:
- production from bone marrow
- distribution in marginating and circulating pools
- migration into tissues
for a steroid leukocytosis and a physiologic leukocytosis, write out the “textbook” changes you would see for the following values:
- total WBC
- segmented N
- band N
- Lymphocyte
- monocyte
- Eosinophil
steroid leukocytosis:
- increased total WBC
- increased segmented N
- WRI slightly elevated band N
- decreased lymphcytes
- increased monocytes
- decreased eosinophils
physiologic leukocytosis:
- increased total WBC
- increased segmented N
- WRI band N
- increased lymphocyte
- WRI increased monocyte
- WRI eosinophils
with a steroid or stress leukocytosis, are the actual numbers of cells changing? Why do we see increases in cell numbers?
there are no actual changes in absolute numbers, just changes in blood concentration (the cells are moving to circulation causing an increased value)
what are 3 main reasons you can have a steroid or stress leukocytosis?
- glucocorticoid release due to:
- stress of illness
- hyperadrenocorticism
- glucocorticoid therapy (exogenous steroids)
why do we see neutrohpils increasing with a stress/steroid leukocytosis?
the neutrohpils shift from marginating pool to circulatin pools, there is decreased tissue migration, and increased release of the storage pool from the bone marrow
in a stress/steroid leukocytosis, how much of an increase in segmented neutrophils will you see?
can reach 2-4x the upper reference limit in dogs
why do we see lymphopenia in a stress/steroid leukocytosis?
shift from circulating pool to lymph nodes or bone marrow (short term), or lymphotoxic effects, decreased lymphopoiesis, and lymphocytolysis (chronic/long term)
why is there a monocytosis in a stress/steroid leukocytosis?
the mechanism isn’t known, could be shifting from maginating pool to circulating pool
an “excitement” leukogram, aka a physiologic leukocytosis, is due to
epinepherine release due to fear, excitment, strenuous exercise, and only lasts 20-30 minutes
what are the two things youll see on the CBC that tell you “hmm yeah okay thats probs a physiologic leukocytosis”
- increased neutrophils (shift from marginating pools)
- increased lymphocytes (maybe from the spleen/excitment?)
A cat named Barris comes to your clinic to get neutered and he is very fractious and hates you! On his pre anesthetic CBC, you note high WBCs, high Segs, and high lymphs. What leukogram process is this?
- leukocytosis, neutrophilia, lymphocytosis
probably physiologic (epinepherine) leukocytosis
A cat named mister pickles who is 15 years old and has been vomitting for a few months. You preform a geriatric screen, and you find he has low lymphocytes. What leukogram pattern is this?
- lymphopenia
steroid leukocytosis due to stress from chronic illness
what can mild hyperglycemia indicate? How could you determine if it is transient or not?
- could be excitment or fright due to epinepherine release
- steroid associated due to glucocorticoids
- post prandial (after a meal)
- you could take a sample later on to see if the glucose levels go down
