White blood count

what clinical condition involves evaluating the degree of bone marrow response to infection using a leukogram?

convalescence

beyond infection, what category of disease can a leukogram help identify?

cancers

a leukogram can help differentiate between bacterial and_____ infections.

viral

what is a primary advantage of performing hand counts for white blood cells regarding equipment?

inexpensive equipment is needed

what factor is required for hand counts to yield reproducible and accurate results?

an experienced technician

name one disadvantage of manual white cell counting related to the technician’s training?

learning curve (or requires skill)

which physiological state can negatively affect the accuracy of a manual white blood cell count?

severe dehydration

what is a major advantage of machine counters in terms of technician workflow?

“walk away” technology (fast operation)

what comprehensive task do machine counters perform in addition to total cell counts?

cell indices and differentials

identify a financial disadvantage associated with using automated machine counters.

they are expensive and require reagents

what is the specific name of the system often used for manual white blood cell counting?

unopette system

in manual counting, what is the specific purpose of the lysing solution?

it eliminates red blood cells

what is the standard depth of a manual counting chamber?

0.1 mm

in the manual counting chamber, how many corner boxes should be counted before repeating for other corners?

1

what feature of a mechanical hand counter alerts the technician that the differential is complete?

a bell sounds when 100 cells are reached

white blood cells include mature and immature neutrophils, lymphocytes, monocytes, eosinophils, and_____.

basophils

what does the suffix: -penia mean?

decreased number of cells

what suffix is used to denote an increased number of cells?

-cytosis (or -philia)

what is leukopenia?

decreased total white blood cell count

what term describes a decrease in all blood cell lines?

pancytopenia

what is leukocytosis?

increased

what is leukemia?

neoplastic cells in the blood

what is the threshold for a leukemoid response in WBCs?

greater than 50,000 / per microliter

a leukemoid response is marked leukocytosis that is usually the result of______.

inflammation

what are lymphoproliferative disorders?

condition where lymphocytes or plasma cells proliferate abnormally

what are myeloproliferative disorders?

neoplastic bone marrow disorders involving proliferation of one or more cell lines

what is the typical shape of a mature neutrophil nucleus?

irregular and elongated

what structures connect the different lobes of a mature neutrophil nucleus?

filaments

how is the chromatin characterized in a mature neutrophil?

clumped

neutrophils have_____ staining granules.

neutral

what is the primary functional classification of neutrophils?

phagocytes

which substance in neutrophil granules binds iron to make it unavailable for bacteria?

lactoferrin

what is the function of hydrolases within neutrophil granules?

they degrade proteins

approximately how often are all blood neutrophils replaced daily?

2.5X daily

at what rate does human bone marrow produce neutrophils?

about 80 million/min

what color is the cytoplasm in a toxic neutrophil?

bluish

what are Dohle bodies?

angular-blue gray granules found in the cytoplasm of toxic neutrophils

what happens to the size of a neutrophil when it exhibits toxicity?

the cell increases in size

what does the presence of neutrophil toxicity signify clinically regarding the bone marrow?

rapid replication in response to infection

toxicity in neutrophils causes the cytoplasm to_____, creating small clear spaces.

vacuolate

what are band neutrophil?

an immature neurtophil

what is the nuclear shape of a band neutrophil?

horseshoe shaped with rounded ends

according to the 1/3 rules, what defines a segmented neutrophil over a band cell?

the nuclear indentation is greater than 1/3 the width of the nucleus

what color do eosinophil granules stain with acidic dyes?

red

eosinophil numbers increase in response to the release of_____.

histamine

name two common clinical conditions associated with eosinophilia.

parasitism and allergies

what is the distinct shape of granules in feline eosinophils?

rod shaped

which species has large, oval eosinophil granules that pack the cytoplasm and stain orange-red?

horse

what is unique about the size of canine eosinophil granules within the same cell?

they vary in size

what type of dye (methylene blue) stains basophils dark blue?

basic dyes

how common are basophils in the peripheral blood of healthy animals?

very rare

basophils degranulate in response to_____.

inflammatory mediators (chemicals)

unlike neutrophils, basophils are not______.

phagocytic

what anticoagulant is found in basophil granules?

heparin

what is the characteristic background color of basophil cytoplasm?

lavender gray

what is neutropenia?

a decreased number of neutrophils

what is lymphocytosis?

an increased number of lymphocytes

what is the function of lysozyme found in neutrophil granules?

it acts as an enzyme to digest bacterial cell walls

what is the nuclear characteristic of canine basophils compared to other species?

they often have a long, ribbon-like nucleus with fewer granules

which WBC type is primarily responsible for attacking parasites directly?

eosinophils

in which tissue do eosinophils typically migrate during inflammatory reactions?

the tissues (extravascular space)