Cross Species - White Blood Cell Parameters Flashcards
what cells are granulocytes?
neutrophils, eosinophils, & basophils
what cells are mononuclear cells?
lymphocytes & monocytes
what is the half life of neutrophils? how long does production in the bone marrow take?
first defense against bacterial pathogens - 10-15 hours & production takes 3-5 days
what is margination in regards to neutrophils?
adhesion to the blood vessel endothelium - these aren’t counted on the CBC
what is the ratio of marginated to circulating neutrophils? what about in cats?
1:1, exception in cats is 2-3:1
T/F: normally, only mature/segmented neutrophils are in circulation
TRUE
endogenous/exogenous glucocorticoids & epinephrine in cats & horses cause what to happen to the neutrophils?
release of marginated pool & rapid increase in circulating neutrophils - main component of stress/physiologic leukogram
what are the 2 main causes of an increased neutrophil count on a CBC?
any source of inflammation/infection causing a release of neutrophils from the bone marrow storage pool & glucocorticoid/epinephrine response with a release of marginated neutrophils
what are the 4 main causes of a decreased neutrophil count on a CBC?
viral infections, inflammation/infection with increased tissue migration (migration most common), bone marrow disease (toxicity, leukemia, & aplasia), & chemotherapy administration
what are the characteristics of a left shift?
increase in number of immature neutrophils - often concurrent with toxic change due to an increase in production in the bone marrow & premature release secondary to more significant inflammation/infection
what is a band neutrophil?
immature neutrophil - lack of nuclear segmentation
what is a degenerative left shift?
more bands than mature neutrophils in circulation - from severe infection/inflammation (bacterial sepsis in foals or endotoxemia in adult horses)
what is the typical appearance of an eosinophil?
pink/orange staining cytoplasmic granules
what are some causes of eosinophilia?
type I hypersensitivity reaction, parasitism, mast cell tumors, hypoadrenocorticism, & idiopathic in rottweiler’s/cats
what is the main cause of eosinopenia?
stress leukogram
T/F: low numbers of basophils are seen in healthy cow/horse blood & are rarely seen in healthy dogs/cats
TRUE
what is the most numerous circulating WBC in cattle & rodents?
lymphocytes
where are lymphocytes produced?
lymph tissue - lymph nodes, spleen!!! not bone marrow!!!
T/F: lymphocytes are the smallest leukocyte
TRUE
T/F: lymphocytes can exist in circulation for days to weeks
TRUE
what other cells may look like lymphocytes on a CBC?
nRBC, neoplastic cells (myeloid or lymphoid leukemia)
what are some causes of lymphocytosis?
antigenic stimulation, physiologic response to epinephrine in stressed cats, horses, & some dogs, animals under 6 months old, bovine leukosis, exercise-related in horses, addison’s, & chronic lymphocytic leukemia (dogs & cats)
what is the main cause of a lymphopenia?
response to glucocorticoids (stress leukogram)
when are reactive lymphocytes seen? how do you differentiate them from lymphoblasts?
immune response - they are deeper blue with more cytoplasm +/- clear cytoplasmic vacuoles - you will only see blasts with hematopoietic neoplasia (acute leukemia & lymphoma)
T/F: blood monocytes are identical to tissue macrophages
TRUE
what are some causes of a monocytosis?
chronic inflammatory/infectious disease & respone to glucocorticoids (stress leukogram)
what do mast cells look like?
round, eccentric nucleus that typically stains liighter than dark purple cytoplasmic granules
when may mast cells be seen in the blood?
type I hypersensitivty, severe inflammation, lymphoma, & mast cell tumors
what is the common pattern of a stress leukogram?
due to cortisol - mature neutrophilia, lymphopenia, monocytosis (uncommon in catsm horses, & cattle), & an eosinopenia
what is the common pattern of a physiologic leukogram?
due to epinephrine in horses & cats - mature neutrophilia & lymphocytosis
T/F: a CBC can be normal with inflammatory/infectious/immune-mediated disease
TRUE
what is the common pattern of an inflammatory leukogram?
neutrophilia +/- left shift, +/- toxic change, +/- monocytosis/lymphopenia/eosinopenia
why do you always need to do a manual platelet count?
platelet clumping is normal & can significantly decrease the automated count
how do you perform a manual platelet estimation?
evaluate on 100x field, count platelets in 10 fields & average, average platelet count X 15,000 = estimated count
what are the normal platelet counts of dogs, cats, horses, & ruminants?
dogs & cats: greater than 200,000, horses: greater than 100,000, & ruminants: greater than 400,000
spontaneous bleeding can occur if platelets get below what level?
30,000
what is a primary cause of thrombocytosis?
myeloproliferative disease
what is a secondary cause of thrombocytosis?
neoplasia, immune-mediated disease, & chronic inflammatory disease
what is the most common cause of decreased platelets in dogs?
IMTP
what are some causes of thrombocytopenia in dogs?
decreased bone marrow production, increased consumption (DIC), sequestration in spleen/microvasculature, & increased detruction (IMTP)
what does an increase in MPV indicate?
regenerative response
what causes spurious thrombocytopenia?
platelet clumping
