Hematology - Scut Monkey and Lecture No. 1 Flashcards
true or false; wbc is highest at birth and then tapers to adult levels by puberty
true
does hct always reflect the blood loss? why or why not?
no b/c plasma and rbc are lost in equal amounts during hemorrhage so the hct does not immediately reflect the loss sometimes not for 2 to 3 hours later
what determines cell age for PMNs?
the degree of nuclear lobulation (younger you are, less lobes you have)
more than 20 five-lobed cells/100 WBCs is indicative of what?
megaloblastic anemia
bacterial infection, toxemia and hemorrhage are indicative of what type of shift?
left shift
what are three common examples of right shift?
liver disease, megaloblastic anemia, iron deficiency anemia
what tube top color is used for a retic count?
lavendar
true or false: the retic count is part of cbc
nope; false
reticulocytes are juvenile rbc’s with remnants of what?
cytoplasmic basophilic RNA
bsophilia of the RBC cytoplasm on a Wright stain is indicative of the presence of what?
reticulocytes
what is the formula for the corrected reticulocyte count?
reported count x patients hct/normal hct
the corrected reticulocyte count is a great indicator of what?
erythropoietic activity
what is the normal corrected reticulocyte count typically about?
less than 1.5%
normal bone marrow responds to decrease in erythrocytes with an increase production of what?
retics
PMN depression when mild is referred to as what? when severe?
neutropenia; agranulocytosis
what is hematocrit really defined as?
The ratio of red blood cells to the total volume of blood.
what is known as the amount of hemoglobin in the average red cell?
MCH (mean corpuscular/cellular hemaglobin)
how do you define the MCV?
mean corpuscular volume/measure of the average red blood cell volume (i.e. size).
what is defined as the average concentration of Hbg in a given volume of red blood cells?
mean corpuscular hbg concentration (mchc)
hemoglobin/hematocrit is the formula for what?
mchc
the term poikilocytosis means what?
irregular RBC/wbc SHAPE
what does the term anisocytosis mean?
irregular RBC/wbc SIZE
only test used to monitor low molecular weight heparin.
anti-xa test (blue tube top); also used to monitor heparin therapy when PTT not available
test used to document neutralization of heparin
activated clotting time (ACT)
test for the presence of antibody on the patient’s cells and for the screening for autoimmune hemolytic anemia
Coombs test, direct
test for antibodies against red cell antigens in the patient’s serum; check for cross-match before transfusion
coombs test, indirect
what is the most common hereditary coagulation disorder in the US?
factor V leiden (activated protein c resistance)
used to evaluate the extrinsic coagulation system.
PT
used to evaluate the intrinsic coagulation system
PTT, aPTT
what gauge needle should be used when collecting venous blood? if this is not available, should you go higher or lowe?
22 - higher
why is it not advised to use small needles when trying to collect venous blood?
b/c small needles cause hemolysis
routine cbc is collected in a tube of what coloring with what special ingredient added?
purple; EDTA
how is the fresh blood collection to be shaken once collected with EDTA? why is this?
shaken gently back and forth as to avoid hemolysis
most samples that are sent for coagulation are sent with what tube top coloring?
blue/citrate
true or false: capillary heel and finger sticks can yield a falsely low hematocrit? what is the reading produced after milking these areas?
true; milking leads to readings that are falsely high
true or false: wright stain blood smear is automatically done along with the automated cell count
false - must be requested
what is the main reason to order a wright stain?
main advantage is that it identifies abnormal cells; in more detail, it provides a manual differential leukocyte count (useful for anemia and certain infections)
mcv and hemoglobin concentration are two factors used to calculate what?
hematocrit
true or false: an acute bleed will be normocytic for the first couple of hours.
true - will have normal hematocrit although volume measures will be dropping
predominance of immature white cells is called _____ and can be indicative of the body responding to loss by increasing the rate of new cell production - while older cells are the ones being lost
shift to the left
a predominance of cells with four or more lobes is called what?
shift to the right
a single six or seven lobed PMN would be diagnostic for what?
megaloblastic anemia
what do terms “bands”, “stabs” and “segs” refer to?
first two are immature wbc, the last references mature wbc
about what percentage of bands being present would be indicative of a “left shift”
10 to 12%
stress reaction can be indicated in a shift to the left or to the right?
right shift
what is the presence of basophilia of the RBC cytoplasm on a Wright Stain called? (the presence btw is indicative of retics)
polychomasia
what are the 7 differentials for an increased eosinophil count?
NAACP: neoplasm, allergies, asthma, addison’s, collagen-vascular disease, and parasites and pulmonary disease.
what will steroids do the the level of eosinophils?
decrease
what are subsets of lymphocytes most useful for diagnosing?
AIDS, leukemia, lymphoma
true or false: a significant portion of the US population has a decreased lymphocyte count as their normal
true (22%)
what is the most likely cause of >20% presence of atypical lymphs?
mononucleosis – other possible causes include CMV, toxo, or malignancy
what is the most likely cause of lymphocytes being down (less than 20%)?
rickettsial infection, or common viral infections
monocytes will be increased during what kind of infections?
bacterial infections such as subacute bacterial endocarditis, TB, etc.
what is the approx. normal male hct? female?
40-54% and 37-47% | 50 to 60 and 40 to 50 if easier
what does megaloblastic anemia do to MCH? what about iron deficiency anemia
increase; decrease
what does severe prolonged dehydration do to mchc?
increases it
this is known as the measure of degree of anisocytosis (the variation in size of rbc)
red cell distribution wideth
abnormalities of function of this type of cell are assessed by bleeding time and platelet aggregation - what is the cell type?
platelets
these type of cells are specific monoclonal antibodies
lymphocyte subsets
when using lymphocyte subsets to diagnose AIDS, what is the marker you are looking for?
CD4/CD8 ratio less than one
