2.6, 2.7, 2.8 WBC Flashcards
what cell appears largest on a slide
monocyte
what is the neutrophil:lymphocyte ratio in ruminants
1:1
how long does it take neutrophils to develop in the bone marrow
5-7 days
what is the process of neutropoiesis from stem cells
stem cell -> myeloblast -> promyelocyte -> myelocyte -> metamyelocyte -> band neutrophil -> neutrophil
what are the two compartments of neutrophils in the blood
circulating neutrophil pool (CNP) and marginating neutrophil pool (MNP)
what is the clinical significance of CNP and MNP
when you take a blood sample you do NOT capture the MNP
what is the ratio of MNP:CNP in most species
1:1
what is the ratio of MNP:CNP in cats
3:1
what is the half-life of neutrophils in blood
12-24h
what is neutrophilia
increase in circulating mature, segmented neutrophils
what are the five mechanisms of neutrophilia
1) physiologic response
2) stress leukogram
3) acute inflammation
4) chronic inflammation
5) necrosis/neoplasia
the epinephrine (physiologic) response is characterized by
mild neutrophilia and mild lymphocytosis
what is the mechanism behind the physiologic response
marginating neutrophils move into CNP; lymphocytes stay in circulation longer
the physiologic response occurs more often in
younger animals
stress leukogram is characterized by
mild to moderate neutrophilia, monocytosis, lymphopenia, eosinopenia
what is the mechanism behind a stress leukogram
release of bone marrow storage pool of mature neutrophils; longer circulation time; decreased margination; lymphocytes retained in lymph nodes
acute inflammation is characterized by
neutrophilia with moderate to marked left shift
what is the mechanism behind acute inflammation
depletion of segmented neutrophils and release of younger neutrophils from the bone marrow
chronic inflammation is characterized by
marked neutrophilia with variable left shift
what is the mechanism behind chronic inflammation
bone marrow has more time to upregulate neutropoiesis
what is tissue necrosis/neoplasia characterized by
mild to marked neutrophilia often with a left shift
what is the mechanism behind tissue necrosis/neoplasia
release of cytokines that increase production of neutrophils
dogs and cats produce a __________ of neutrophilia in response to inflammation in comparison to horses and ruminants
increased magnitude
you can equate a neutrophil count of _____ in a horse or ruminant to a neutrophil count of ______ in a dog or cat
30; 100
the degree of neutrophilia correlates with; the degree of left shift correlates with
the intensity of the inflammatory stimulus; acuteness
what is a consideration r.e. draining/open vs closed lesions
in open lesions will not see as high of a count
what are leukemoid reactions
very intense neutrophilia that resembles a leukemia
a patient is treated by ovariohysterectomy for a closed pyometra; the next day, what do you expect to happen to the neutrophil count and why?
expect more severe neutrophilia; the bone marrow would have undergone hyperplasia, so lots of neutrophils will be released, but now they have nowhere to go to, so they stay in the CNP and increase the count
what are two broad causes of neutropenia
decreased production of neutrophils; tissue demand of neutrophils exceeds bone marrow storage