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415 Cards in this Set
- Front
- Back
why use a standard red top tube
|
standard CBC/Chem, endocrine, serology
|
|
why use a serum separator tube?
|
stops glucose from being degraded over time
|
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Anemia
|
A decrease in the hemoglobin value, the packed cell volume, or the erythrocyte count of more than two standard deviations below the mean normal.
|
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why use EDTA
|
cbc/wbc/rbc/platelets, binds Ca to prevent coagulation
|
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Anisocytosis
|
Variation in the size of cells, usually the erythrocytes.
|
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what is important when using EDTA?
|
use the rigth size tube for amount of blood, otherwise RBCs will shrink
|
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what is special about heparin as an anticoagulant?
|
only one that does not bind Ca
|
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Aplastic
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Cessation of blood cell formation
|
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What does the PCV/Hct measure & which is more accurate?
|
% of whole blood that is RBCs
PCV considered more accurate |
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electrophoresis: what does the height of the peak indicate?
|
concentration of protein
|
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Band form
|
a granulocyte with a nucleus that is unsegmented and ribbon like - stab, nonfilamented - juvinal
|
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What factors can cause errors in measured RBC count?
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species RBC size variation, counting of large platelets, not counting small RBCs (microcytes), or agglutination
|
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What factors can artifically increase measured Hb concentration?
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lipemia, Heinz bodies, WBC > 50,000/µl, hyperbilirubinemia
|
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what is mesured on routine electrophoresis?
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total protein, albumin, globulin
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Basophilic strippling
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Erythrocyte that shows blue staining, basophilic granules scattered throughout.
|
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is globulin a measured or calculated value?
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calculated: T prot- alb
|
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What is MCV?
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mean corpuscular volume = average RBC volume (size)
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Buffy coat
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The layer of leukocytes, thrombocytes and nucleated erythroncytes, if any, that collect immediately about the erythrocytes in sedimented or centrifuged whole blood.
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alpha globulins
|
acute phase proteins. Made by the liver in reponse to inflammation. They are produced quickly and are produced as long as there is active inflammation
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What is MCHC?
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mean corpuscular hemoglobin concentration = average conc. of Hb per RBC volume
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Color index:
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the ration between the ammount of hemoglobin and the number of erythrocytes
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beta globulins
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a mix- some acute phase proteins, lipoproteins, complement, some immunoglobulins
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Crenation
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Shrinkage of cells in a hypertonic souution with the formation of irregular margins and a number of prickly points. Also seen in smears caused by dirty glassware, slow drying, extreme temperatures, and poor smearing technique.
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What is RDW?
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random distribution of RBC weight: distribution of RBC's based on their volume (size)
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gamma globulins
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immunoglobulins
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what does an increase of gamma globulins indiciate?
|
immune response
|
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Dohle bodies
|
Small (1 to 2 microns) roiund or oval, fray-blue bodies in the cytoplasm of neutrophic leukocytes thought to be due to incomplete utilization of RNA during maturation of the cytoplasm.
|
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What is the name for an
a) increase b) decrease in MCV? |
a. macrocytosis
b. microcytosis |
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why do a TP from a refractometer and a CBC not match?
|
measured in different ways from different samples
|
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Erythrocytopenia
|
A decreased number of erythrocytes in the perpheral blood
|
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What is the name for an
a) increase b) decrease in MCHC? |
a. hyperchromasia
b. hypochromasia |
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Erythrocytosis
|
The presence of an increased srythrocyte count above normal and associated with an increased total blood volumne
|
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fibrinogen
|
acute phase reactants that is measured to detect inflammation, particularly in horses and cattle
|
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Erythropoiesis
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The production of erythrocytes
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What is the name for any abnormally shaped RBC?
|
poikilocyte
|
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Fibrin
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The end product of the clotting mechanism, which forms a network of fibers that enmesh the formed elements of blood
|
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how is fibrinogen measured
|
it precipitates out when the sample is heated, so the protein is measured before and after heating
|
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What is an acanthocyte & with what disorders is it associated?
|
spiculated RBC w/ single or multiple, irregular, blunt, rounded projections
liver dz (more in cats), microangiopathy, HSA |
|
Granulocyte
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A leukocyte that contains specific cytoplasmic granules(neutrophilis, eosinophils, basophils) regardless of the stage of differentiation.
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what can increalse productoin of fibrinogen?
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inflammation
|
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Granulocytosis
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Presence of increased numbers of granulocytes in the blood.
|
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What is an keratocyte & with what disorders is it associated?
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spiculated RBC w/ 1 or 2 pointed projections
Fe deficiency, liver disorders |
|
Heinz bodies
|
An intraerythrocytic mass of denatured globin, irregular in shape and appearing as refractile granules when slightly out of focus. This latter property is responsible for their being called erythrocyte refractile bodies.
|
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most common cause of decreased fibrinogen?
|
excesssive consumption during coagulation in DIC
|
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What is an echinocyte & with what disorders is it associated?
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spiculated RBC w/ numerous short, evenly shaped surface projections
snake bite envenomation, crenation, dehydration |
|
what does the serum concentration of albumin reflect?
|
a balance between hepatic synthesis and normal catabolism
|
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Hemolysis
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Descruction of erythrocytes by dissolution or lysis.
|
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What is an spherocyte & with what disorders is it associated?
|
small dense RBC lacking central pallor
IMHA, Heinz body anemia, transfusion |
|
Howell-Jolly bodies
|
Small, round, densely staining bodies in the srythrocytes that are considered to be nuclear remnants and are usually eccentric in location.
|
|
pathologic processes tthat affect serum concentration include:
|
changes in hydration status, changes in the rate of hepatic synthesis, and processes leading to an accelerated loss of albumin.
|
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Hyperchromasia and hypercromatic
|
Terms which when applied to the microscopic appearance of a cell or cells of the srythrocytic series, indicate that the cells seem to have a more intense hemoglobin color due to an increased thickness of the observed cell
|
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What is an schistocyte & with what disorders is it associated?
|
fragmented RBC
DIC, microangiopathy |
|
Hyperchromic
|
Because of a significant increase in mean corpuscular hemoglobin is not known to occur, it is recommended that this term be avoided
|
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what can reduce hepatic syntehsis of of albumin?
|
hepatic failure, starvation/malnutrition/aa deficiency and it can be reduced in response to acute or chronic inflammation
|
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What is an eccentrocyte & with what conditions is it associated?
|
RBC w/ condensed Hb in one area of cell
oxidative damage to Hb |
|
albumin is a ____ acute phase protein
|
negative
|
|
What is a nucleated RBC & with what conditions is it associated?
|
Immature RBC w/ a nucleus in peripheral blood
intense BM stimulation, BM injury, after splenectomy, lead poisoning |
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Hypochromasia and Hyperchromatic
|
indicate that the cells show a significant decrease in density of the characteristic hemoglobin color for the stained or unstained cell. This may be due to either thinness of the cell, decreased concentration of hemoglobin or both
|
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what are the main clinically significant globulins?
|
immunoglobulins made by lymphocytes (and acute phase proteins made by the liver)
|
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Hypochromic
|
An adjective describing a blood picture in which the srythrocytes have a mean corpuscular memoglobin concentration or saturation index and usually a mean corpuscular hemoglobin of color indx more that two standard deviations below the mean normal determined by the same method on the blood of healthy animals of the same age and sex group
|
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What is a Howell Jolly body & with what conditions is it associated?
|
Basophilic nuclear remnants usually near edge of RBC (Romanowsky stains)
accelerated RBC production |
|
what can result in increased globulins?
|
acute or chronic inflammation, hydration status. Some tumors
|
|
What is a Heinz body & with what conditions is it associated?
|
Round structures (representing denatured Hb) on internal RBC membrane (NMB stain)
oxidative damage to Hb: onions, acetaminophen, Red Maple (horses), propofol (w/ repeated use), 1-2% clinically asymptomatic in cats |
|
when does the A:G ration become useful?
|
when more than one process is occuring at the same time
|
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Leukemia
|
Neoplastiv disease arising in hemopoietic tissue in which the type cells appear in the blood.
|
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What is basophilic stippling & with what conditions is it associated?
|
RBCs containing residual RNA, appear as multiple, small blue dots w/ Romanowsky stains
ruminants: regeneration other species: lead poisoning |
|
Leukocytosis
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An increase in the number of circulating leukocytes above the normal range
|
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if the disease affects both albumin and globulin, what happens to the ratio
|
remains the same
|
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Leukopenia
|
A decrease number of circulating leukocytes below the normal range
|
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What is agglutination & with what conditions is it associated?
|
Grape like aggregation of RBCs that will NOT disperse w/ saline dilution
IMHA |
|
Macrocyte
|
An srythrocyte having a diameter exceeding that of the normal range.
|
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what affect does dehydration have on the ratio?
|
ratio unaffected, both increase equally
|
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Macrocytic
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Erythrocytes have a mean corpuscular volume exceeding by more that two standard deviations the mean normal determined by the same method on the blood of healthy animals of the same age and sex group when this condition is not doe to riculosytosis alone.
|
|
What is Rouleaux formation & with what conditions is it associated?
|
Grouping of RBCs resembling a stack of coins that disperses w/ saline dilution
- horse: normal - cat, pig: slight amount normal - other: chronic inflammation, multiple myeloma |
|
Microcyte
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An erythrocyte having a diameter below the normal range
|
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what will happen to the ratio if the animal is dehydrated and has chronic inflatmmation?
|
both will increase by the glubulin will increase relatively more, so the ratio will decrease
|
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Microcytic
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An adjecitive describing a blood picture in which the srythrocytes have a mean corpscular volume of volume index more that two standard deviations below the mean normal determined by the same method on the blood of healthy animals of the same age and sex group
|
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What is crenation & with what conditions is it associated?
|
RBC w/ even distribution of sharp spikes (shape change occurs in all cells in given area)
artifact (old blood, delayed drying of blood film, improper anticoagulant ratio) |
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Neutropenia
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Deficency of neutrophilic leukocytes in the blood
|
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what is measured directly from an automated instrument?
|
total nucleated cell count, hemoglobin, RBC count, MCV, platelet count
|
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Neutrophilia
|
An increase in the total number of neutrophils in the blood
|
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What are 4 parasites that may be found w/in RBCs?
|
Anaplasma
Babesia Mycoplasma Ehrlichia |
|
three calculate values
|
HCT, MCHC, RDW
|
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Normocytte
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An erythrocyte having a normal diameter
|
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What is polycythemia?
|
increase RBC count, PCV, Hb
|
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Normocytic
|
Blood picture in which the erythrocytes have a mean corpuscular voulmne with in the normal range
|
|
what should you always do when running bloodwork?
|
perform a blood smear to look at cell morphology
|
|
Pelger-Huet anomaly
|
A rare herediatary condition associated with myeloproligerative disorder where neutrophils lack the usually nuclear segmentation
|
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What is relative polycythemia?
|
increased PCV, & Hb with normal total RBC mass
|
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Poikilocyte
|
An erythrocyte with an abnormal shape, not to be confused with distortion that results from faulty technique
|
|
impedance method
|
cells impede current passing through aperture- counts and sizes particles. The main discriminator is size.
|
|
Polychromasia, polychromatic, polychromatophilia
|
Erythrocytes that show a faint bluish tint due to a mixture of the characteristic colors of hemoglobin and basophilic erythrocytic cytoplasm.
|
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What are the 2 main causes of relative polycythemia?
|
dehydration: ↑ PP, dry skin & mucous mems, ↑ BUN, creatinine, USG (can calculate PP:fibrinogen ratio in LA)
splenic contraction: all parameters normal, may occur in horses & cats |
|
Polycythemia
|
A state of the blood characterized by an increased number of erythrocytes
|
|
optical method-flow cytometry
|
laser hits each cell; light scatter counts, sizes, IDs cells
|
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Reticulocyte
|
Any nonnucleated cell of the erythrocytic series containing RNA, which when supravitally stained with new methlene blue or brilliant cresyl blue will have discernible granules or a diffuse network of fibrils.
|
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What is absolute polycythemia?
|
increased PCV & Hb w/ ↑ in total RBC mass d/t ↑ erythropoiesis (less common than relative)
|
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Rouleaux formation
|
The arrangement of erythrocytes in a roll or column, with their flat surfaces facing, in which they appear as figures resembling stacks of coins.
|
|
common sources of error with blood analyzers:
|
RBC size overlap (species, esp cat), giant platelets, clumped platelets. Sample problems: agglutinatoin, lipemia, hemolysis
|
|
What is the cause of primary absolute polycythemia?
|
bone marrow disorder --> uncontrolled RBC production (RARE)
|
|
Shift to the left
|
An increase in the immature forms of the granulocytic series in the blood
|
|
dog RBC size
|
60-72fl
|
|
Shift to the right
|
An increase in the percent of older cells (hypersegmentation)
|
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What are the 2 causes of secondary absolute polycythemia?
|
both cause increased EPO production
appropriate: d/t chronic hypoxia (CV dz, pulmonary dz, etc.) inappropriate: : d/t renal dysfunction or neoplasia that produces ↑ EPO can be iatrogenic: too much epogen |
|
cat, horse, cow RBC size
|
39-52 fl
|
|
Spherocyte
|
A spheroid erythrocyte of decreased diameter in relationship to its volume and having the microscopic appearance of a hyperchromativ microcyte
|
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What is anemia?
|
↓ RBC count, PCV, & Hb
|
|
sheep rbc size
|
25-35 fl
|
|
What 3 schemes are used to classify an anemia?
|
RBC indices (MCV, MCHC)
BM response (regenerative vs. non-regenerative) underlying cause |
|
llama rbc size
|
21-29 fl (note oval shape)
|
|
Toxic Neutrophil
|
A neutrophil characterized by toxic granules, basophilia of the cytoplasm, vacules, or condensation of nuclear chromatin.
|
|
What are the 3 main underlying causes of anemia, what are the associated changes in plasma protein, & how would you diagnosis each?
|
↓ RBC production
- PP NORMAL or ↑ (d/t inflammation) - dx: reticulocytes, bone marrow blood loss -very early in acute blood loss, PCV will be NORMAL b/c both RBCs & plasma being lost at same proportion -later, interstitial fluid moves rapidly into blood ↓ PCV, ↓ PP -dx: hx, lesions ↑ RBC destruction (lysis) -may be intravascular or extravascular hemolysis -PP NORMAL or ↑ (d/t inflammation) -dx: icterus, RBC changes |
|
goat rbc size
|
15-25 fl
|
|
What are some causes of microcytosis?
|
iron deficiency
PSS normal in Akitas, Japanese Shiba implies abnormal Hb synthesis --> smaller cells |
|
What are some causes of macrocytosis?
|
regeneration
FeLV may be normal in Poodles false (d/t agglutination) assoc. w/ increased erythropoeisis --> release of retics (larger than mature RBCs) |
|
What are some causes of hypochromasia?
|
Fe deficiency
reticulocytosis |
|
What are some causes of hyperchromasia?
|
hemolysis (true hyperchromic cells don’t exist)
|
|
What is the most common type of anemia based on RBC indices?
Is it usually regenerative or non-regenerative? |
normocytic normochromic
usually non-regenerative |
|
ddx for microcytic hypochromic anemia
Is it usually regenerative or non-regenerative? |
Fe deficiency (most common), PSS, anemia of chronic dz, etc.
poorly or non- regenerative |
|
ddx for macrocytic hypochromic anemia
|
regenerative anemia (reticulocytosis)
|
|
in MCHC?"
|
"a. hyperchromasia
|
|
ddx for macrocytic normochromic anemia
|
FeLV (altered RBC maturation), may be normal in miniature & toy poodles
|
|
what does a differential leukocyte do and how is it performed?
|
determine percentage of different cell types. Performed on wright stained blood film
|
|
What signs are evidence of regeneration on a blood smear?
|
reticulocytosis
basophilic stippling (bovine) macrocytosis (horse) Howell Jolly bodies anisocytosis |
|
do you use the percentage of leukocytes for interpretation?
|
no, use the absolute number (% * WBC)
|
|
What are the unique factors assoc. w/ regeneration in
a. horses b. cows c. cats |
a. no reticulocytosis, look for macrocytosis, look in bone marrow
b. inconsistent release of retics; look for basophilic stippling c. 2 types of retics -aggregate: similar to dog retics (indicates a recent stimulus (a few days)) -punctate: cells contain dots & not aggregated RNA (indicates a stimulus 1-3 weeks previously) |
|
why should you do a blood film evaluation?
|
look at erythrocyte and leukocyte morphology, confirm automated analyzter results, look for platelet clumps, giant platelets, look for blood parasites and abnormal cells
|
|
What are the 2 major causes of regenerative anemia?
|
blood loss
hemolysis |
|
where should you analyze a blood film?
|
at the monolayer
|
|
What are the early pre-regenerative responses during acute blood loss?
|
↑ blood volume: shift ECF to IV space
↑ RBCs: splenic contraction |
|
what are reticulocytes?
|
immature RBCs that still contain organelles. They stain with vital dyes such as new methylene blue. Correspond to polychromatophils on the wright stained blood film
|
|
why is a reticulocyte count important?
|
to classify anemias
|
|
calculate absolute retics:
|
(% retics in 1000 RBCS) * RBC count
|
|
what can nucleated RBCs be due to?
|
strongly regenerative anemia, splenic dysfunction, marrow injury, etc
|
|
Corrected WBC count
|
nucleated cell count * (100/100+nRBCs)
|
|
absolute nRBC
|
% * TNC count
|
|
how are nRBCs commonly reported?
|
# per 100 WBC
|
|
What other hemogram or chemistry abnormalities are associated w/ blood loss anemia?
|
decreased plasma protein
|
|
What other hemogram or chemistry abnormalities are associated w/ hemolytic anemia?
|
normal or ↑ PP hyperbilirubinemia hemoglobinemia
hemoglobinuria RBC morphology (spherocytes, parasites, Heinz bodies) |
|
What is extravascular hemolysis & what is a commonly associated serum chemistry change?
|
abnormal RBCs phagocytosed by MPS in spleen & liver (more common)
hyperbilirubinemia usually present |
|
What are some causes of extravascular hemolysis?
|
IMHA, oxidative damage, intrinsic RBC defects, parasites
|
|
What RBC morphologic changes are associated w/ IMHA?
|
anisocytosis, polychromasia (regeneration), agglutination, spherocytes, ghost cells, ↑ MCV (d/t retics & agglutination)
|
|
What is the Coomb's test?
|
used to help dx IMHA
detects Ab &/or complement bound to patient’s RBCs positive ≠ 1º IMHA |
|
What RBC morphologic changes are associated w/ oxidative hemolytic anemia?
|
Heinz bodies, eccentrocytes
methemoglobinemia also called Heinz body hemolytic anemia |
|
What is intravascular hemolysis & what are 2 prominent features that help to dx it?
|
RBCs lysed w/in bloodstream: poorer px
hemoglobinemia, hemoglobinuria |
|
What are some causes of intravascular hemolysis?
|
complement mediated, bacterial toxins, parasites, hereditary, chemicals/toxins
|
|
What are some causes of fragmentation of RBCs (subset of intravascular hemolysis)?
|
microangiopathy: abnormal small vessels (see acanthocytes, schistocytes)
ex. HSA, vasculitis DIC: fibrin deposited in vessels (schistocytes) |
|
What CBC findings are consistent w/ nonregenerative anemia?
|
no retics
no polychromasia variable anisocytosis N to ↑ nRBCs N to variable MCV & MCHC hx: chronic |
|
What is the main defect associated w/ non-regenerative anemias?
|
decreased erythropoiesis = hypoproliferative BM d/t inadequate # of precursors or inadequate stimulus
|
|
What are some causes of non-regenerative anemia?
|
Fe deficiency
ACD lack of EPO BM damage myelophthisis |
|
What are some causes of iron deficiency anemia?
|
chronic blood loss: parasites, ulcers (most common)
dietary deficiency: young animals (uncommon) malabsorption: intestinal dz |
|
What lab findings are consistent w/ iron deficiency anemia?
|
microcytic hypochromic anemia
non-regenerative ↓ serum iron ↓ bone marrow iron stores ↓ ferritin (storage form of iron) thrombocytosis: megakaryocytes respond to EPO |
|
What is the most common anemia of domestic animals?
|
anemia of chronic dz
|
|
What lab findings are consistent w/ anemia of chronic dz?
|
initially, normocytic, normochromic
over a long time, can progress to microcytic, hypochromic non-regenerative ↓ serum iron: iron sequestered in MPs normal ferritin thrombocytosis: d/t inflammatory mediators |
|
How could you differentiate non-regenerative anemia as being caused by Fe defeciency or ACD?
|
give patient some iron
improvement = Fe deficiency no improvement = ACD |
|
What is aplastic anemia & what are some causes?
|
depletion of all 3 cell lines in blood & BM
causes: estrogen, infections (Ehrlichia, FelV), drugs, plants, radiation |
|
What are 3 main underlying causes of thrombocytopenia?
|
increased destruction (common)
increased consumption or sequestration decreased production |
|
What are the functions of platelets?
|
plug endothelial lesions, clot formation, release soluble mediators
|
|
How do platelets form & what controls their production?
|
produced by “flaking off” from megakaryocytes
thrombopoietin controls production |
|
What are common causes of thrombocytopenia d/t increased destruction?
|
immune mediated
1º (autoimmune): Abs against self Ag on megakaryocytes &/or platelets 2º: Abs against non-self Ag on platelet surface |
|
What are common causes of thrombocytopenia d/t increased consumption or sequestration?
|
DIC: most common
sequestration (ex. spleen): transient, not common massive hemorrhage: would take huge blood loss |
|
What are common causes of thrombocytopenia d/t decreased production?
|
marrow suppression d/t drugs, toxins, infectious agents, neoplasia, etc.
↓ platelets w/ ↓ WBCs &/or ↓ RBCs |
|
What are some characteristics of platelet regeneration?
|
large platelets
↑ MPV BM: megakaryocytic hyperplasia (↑ # of megakaryocytes) |
|
What are 3 main categories of thrombocytosis?
|
physiologic: common
reactive: common myeloproliferative/neoplastic: rare |
|
What are causes of physiologic thrombocytosis?
|
transient mobilization: minutes to hours (d/t splenic contraction)
exercise & epinephrine |
|
What are causes of reactive thrombocytosis?
|
↑ production by BM d/t:
thrombopoietin erythropoietin (anemia) inflammation |
|
What is Evans' syndrome?
|
concurrent IMHA & IMTP
|
|
In what species are lymphocytes usually more prevalent in peripheral blood than neutrophils?
|
cattle
|
|
What is meant by the term left shift?
|
indicates presence of immature granulocytes (usually neutrophils) in blood
|
|
What is a regenerative left shift?
|
leukocytosis in which mature neutrophils outnumber immature neutrophils
|
|
What is a degenerative left shift?
|
immature neutrophils outnumber mature neutrophils
indicates excessive demand &/or inadequate supply (more guarded px) |
|
What is a leukemoid rxn?
|
very high neutrophil count w/ a severe, but orderly left shift
indicates severe inflammation but a responding bone marrow |
|
What are the CBC changes consistent w/ leukemia?
|
presence of neoplastic hematopoietic cells in circulation
leukocytosis; immature forms: often 1 stage overrepresented; disorderly maturation |
|
What are the functions of neutrophils?
|
chemotaxis: cell migration to site of inflammation
engulfment/killing: release of granule contents (enzymes that kill bacteria) |
|
What are band neutrophils?
|
immature neutrophils that has a nucleus w/ parallel sides
|
|
What are hypersegmented neutrophils?
|
neutrophils w/ 5 or more distinct nuclear lobes
indication of prolonged transit time (glucocorticoids) |
|
What are toxic neutrophils & what 3 morphologic features do they possess?
|
indicate inflammation (↑ demand for neutrophils)
↑ basophilia of cytoplasm, vacuolated (foamy) cytoplasm, Dohle bodies (bluish angular cytoplasmic inclusions |
|
What are the 3 neutrophil pools found in the bone marrow?
|
proliferating pool: contains BM cells capable of division
-time from myeloblast --> metamyelocyte: ~2.5 days maturation pool: contains BM cells NOT capable of division -transit time: ~2.5 days storage pool: contains mature BM cells (subset of maturation pool) -constitutes body’s reserve of neutrophils -usually have ~5 day supply in BM storage -wimpy in cattle |
|
What are the 2 neutrophil pools found in blood?
|
marginated pool: neutrophils that have marginated along blood vessel walls
-same size as circulating pool in dogs, horses, calves -3x larger than circulating pool in cats circulating pool: neutrophils in larger blood vessels moving in the main stream of blood -pool that’s sampled when taking a blood sample for CBC |
|
What WBC characteristics are consistent w/ inflammation w/ a mild to moderate tissue demand (ex. abscess?)
|
neutrophilia +/- left shift, monocytosis, toxic neutrophils may be seen
|
|
What WBC characteristics are consistent w/ inflammation w/ continued tussue demand (ex. pyometra?)
|
neutrophilia w/ regenerative left shift & toxic neutrophils, monocytosis
|
|
What WBC characteristics are consistent w/ inflammation w/ an excessive tissue demand (ex. Salmonellosis?)
|
neutropenia, degenerative left shift, toxic neutrophils
insufficient storage cells for demand & BM has not had time to respond |
|
What are some causes of neutropenia?
|
sequestration
increased margination (ex. endotoxins: lasts 1-3 hrs) decreased production: BM usually reveals myeloid hypoplasia (caused by damage to myeloid precursors): FeLV, feline panleuk, Ehrlichia, toxicities, drugs, neoplasia ineffective production, increased destruction: rare |
|
What is Pelger-Huet Anomaly?
|
hyposegmented nuclei of neutrophils, eosinophils, basophils
normal function concern is not to mistake for a left shift inflammatory process |
|
What is physiologic leukocytosis (epinephrine response)?
|
causes by epi (fear, excitement) or sudden strenuous exercise
response time almost immediate, but is short-lived (~30 minutes) key features: mature neutrophilia, lymphocytosis most pronounced in cats, horses dogs: usually mild neutrophilia only |
|
What is corticosteroid induced leukocytosis (stress response)?
|
caused by either endogenous or exogenous steroids
response takes several hours to develop w/ peak rxns in 4-8 hrs key features: mature neutrophilia, lymphopenia, eosinopenia, monocytosis (not a consistent finding, even in dogs) dogs have most classic response lymphopenia is most consistent & occasionally the only finding |
|
What are some causes of lymphocytosis?
|
epinephrine response
immunological stimulation infectious dz: Ehrlichia, bovine leukemia virus lymphocytic leukemia Addison's: stressed dog lacking a stress response normal in cows, swine |
|
What are some causes of lymphopenia?
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stress response
acute infections (esp. viral) loss of lymph radiation/chemo immunodeficiency (less common) |
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What are the functions of monocytes?
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phagocytosis & degradation of ingested material
present antigen to initiate lymphocyte responses |
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What are some causes of monocytosis?
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think CHRONIC INFLAMMATION 1st!: tissue destruction, necrosis, intracellular or fungal organisms
stress response: esp. in dogs immune mediated disorders |
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What are the functions of eosinophils?
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regulation of type I (immediate) & type III (delayed) hypersensitivity rxns
antiparasitic properties bacterial phagocytosis (less so than neutrophils) activation of plasminogen |
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What are some causes of eosinophilia?
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parasites
hypersensitivity rxns hypereosinophilic syndromes neoplasia |
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What are the functions of basophils?
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hypersensitivity (histamine release)
follow eosinophils possible cytotoxic effects against tumor cells possibly anti-parasitic |
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What are some causes of basophilia?
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w/ eosinophilia: parasites, hypersensitivity, neoplasia
rare to have w/o eosinophilia: basophilic leukemia |
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What is leukemia?
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neoplastic cells of BM origin in circulation --> leukocytosis
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What is lymphoma?
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neoplasm of lymphocytes arising as a solid tissue mass in organs other than BM (ex. lymph node, liver, spleen, GI, etc.)
MUCH MORE COMMON THAN LEUKEMIA |
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What is myeloproliferative dz?
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proliferation of granulocytic, megakaryocytic, erythrocytic, &/or stromal CT cells in BM
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What are myelodysplastic syndromes?
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ineffective hematopoiesis w/ resultant peripheral blood cytopenias (ex. FeLV)
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How is leukemia classified?
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based on natural duration of dz
-acute: very little differentiation of neoplastic cells (mostly blasts); duration of illness is short; poor px -chronic: well-differentiated neoplastic cells; may live for months or years after dx based on cytology -myeloproliferative: neoplastic proliferation of non-lymphoid cells (ex. neutrophils, eosinophils, basophils, monocytes, RBCs, megakaryocytes) -lymphoproliferative: neoplastic proliferation of lymphocytes |
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what is special about the retic count in horses?
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horses do not release retics into peripheral blood
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cats have what two forms of reticulocytes?
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aggregate and punctuate. Aggregates correspond to polychromatophils. Punctuate have distinct dots and no clumping. Aggregate mature to punctuate
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in cats, what is the best indicator of active hematopoiesis?
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aggregate retics
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what color do polychromatophils stain with Wrights?
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blue
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what affect do polychromatophils have on MCV? MCHC?
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increase MCV, decrease MCHC.
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what does increased polychromasia suggest?
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regenerative anemia
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most common cause of hypochromasia in dogs and camelids?
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iron deficiency
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hyperchromasia
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does not exist- increased MCHC does not naturally occur
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breed associated microcytosis
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akita, shiba inu
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one major cause of microcytosis
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portosystemic shunt
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do spherecytes affect microcytosis counts?
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no- they may appear small but usually have a normal volume
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most common cause of macrocytic red cells
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regenerative anemia
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how do spherocytes form in IMHA?
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macrophages ecognize antibody bound to red cells and remove part of the red cell membrane, causing the red cell to reform as a sphere
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what, besides IMHA, can result in spherocytes?
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heinz body anemia, zinc toxicosis, post blood transufsion, microangiopathic injury
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schistocytes
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red cell fragments, resulting from shearing of red cells by intravascular trauma
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schistocytes can occur with _____ due abnormal blood flow and localized DIC. _____ are often present as well
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hemangiosarcoma; acanthocytes
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schistocytes may be seen along with kertocytes in
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severe iron deficiency
|
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three other diseases that can result in schistocytes
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glomerulonephritis, liver dz, heart failure
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keratocytes
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formed from physical or checmical injury to red cell (can be secondary to iron deficiency, oxidative damage, or microangiopathic dz processes)
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keratocytes are susceptible to intravascular trauma and may progress to
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schistocytes
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acanthocytes are thought to result from
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changesi n the lipid content of red cell membranes
|
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acanthocytes hve been associated with
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altered lipid metabolism (lipid dz, hepatic lipidosis) and hemangiosarcoma
|
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echinocytes
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spiculated, numerous short, evenly spaced, uniform projections
|
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echinocytes have been associated with
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renal disease, lymphoma, chemo, electrolyte abnormalilies, and envenomation
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type three echinocytes
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seen with rattlesnake and copperhead envenomation- 24-48 hours after envenomation
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eccentrocytes are the result of _____ and may be seen along with ______
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oxidative injury; heinz bodies
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codocytes
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target cells with no real diagnostic significance
|
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rouleaux vs agglutination
|
agglutination forms grape like clusters rather than "coin rolls". Agglutination can be confirmed with a saline agglutination test (rouleaux will disperse, agglutination witll not)
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what does agglutination strongly suggest?
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IMHA
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heinz body appearance
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small circular structure within or protruding from the red cell. Stain dark blue with vital stains.
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what are heinz bodies
|
denatured Hgb resulting from oxidative damage
|
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species that is more prone to heinz body formation
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cats
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howell jolly body appearance
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small round basophilic inclusions on wright's stained blood film
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when are howell jolly bodies normal
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in small numbers
|
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what do increased numbers of howell jolly bodies indicate?
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increased hematopoiesis (Regenerative anemia) or splenic dysfunction
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basophilic stippling reflects
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aggregated ribosomes in the cells
|
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when can basophliic stippling be seen?
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intensly regenerative anemias in dogs and cats, and any regenerative anemia in ruminants. If no regenerative anemia, can suggest lead poisoning
|
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erythroparasites in cats
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mycoplasma haemofelis and cytauxzoon felis
|
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m. haemofelis apearance
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small rod shaped organisms on the red cell periphery or as ring shaped structures on the cell
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c. felis appearance
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small signet ring shaped piroplasms
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what kind of anemia is associated with c. felis
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non regenerative
|
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erythroparasites in dogs
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mycoplasma haemocanis, babesia gibsoni, babesia canis
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m. haemocanis appearance
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small chains of organisms across the surface of the red cell
|
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effects of dehydration on PCV
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it increases
|
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three basic mechanisms of anemia:
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blood loss, blood destruction, decreased production
|
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how can you tell if an anemia is regenerative?
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there is an appropriate bone marrow response- immature red cells are being released, (marked regeneration will raise the MCV and decrease the MCHC). Need to know reticulocyte count
|
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describe a macrocytic, hypochromic anemia
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increased MCV, decreased MCHC, probably regenerative anemia
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before you decide that an aenmia is non-regenerative, what must you know?
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if enough time has passed for the bone marrow to mount a response
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in ruminants, what degree of reticulocytosis indicates a regenerative response?
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any
|
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corrected retic %
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retic% * (Patient PCV / Normal PCV)
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Normal dog PCV? Cat?
|
dog: 45, cat:37
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10/10 rule of thumb
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if PCV is 10%, retics should equal 10% to be regenerative. If you half the PCV, double the retic count. (in dogs)
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what findings suggest hemorrhage (Acute)?
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low total protein, evidence of bleeding, TCP (marked TCP), acanthocytes/schistocytes
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what findings suggest hemorrhage (chronic)
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evidence of GI hemorrhage, low/normal total protein, thrombocytosis, morphological changes typica of iron deficiency
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morphological changes typical of iron deficiency
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microcytosis, hypochromasia, keratocytes, schistocytes
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what findings suggest hemolysis?
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normal total protein, agglutination, sphereocytes, red cell parasites, hemolyzed serum, hemoglobinuria, icterus, hepatosplenomegaly, many large heinz bodies/eccentrocytes, exposure to known oxidants, schistocytes/keratocytes
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hemolysis may be
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intravascular or extravascular
|
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two signs of intravascular hemolysis
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hemoglobinemia and hemoglobinuria
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which anemias tend to be more strongly regenerative: those due to hemolysis/bleeding into body cavities OR those due to external blood loss
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those due to hemolysis or bleeding into body cavities
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IMHA findings
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severe anemia, strongly regenerative, associated with inflammatory leukogram. Sphereocytes/agglutination often present. Coombs test can be performed.
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Evans syndrom
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IMHA + immune mediated destruction of platelets resulting in TCP
|
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potential complication of severe cases of IMHA
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DIC
|
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any diseases that causes chronic blood loss may result in an ______ anemia
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iron deficiency
|
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DIC is
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uncontrolled activiation of the coagulation and fibrinolytic cascades through the body. There is widespread coagulation AND the potential for bleeding (platelets/coag factors have been consumed). Usually TCP, microangiopathic injury.
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anemia of chronic disease (inflammatory dz)
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mild, non regenerative. Normocytic, normochromic.
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anemia of CRF
|
normocytic, normochromic. Look for clues on Chem panel
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anemia of endocrinopathies
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mild, normocytic, normochronic nonregenertive (hypthyroid, hypoadrencorticism)
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felv induced anemias
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macrocytic, normochromic. Aplastic.
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normocytic/normochronic
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most non regenerative anemias
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macrocytic/hypochromic
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most regenerative anemias
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macrocytic/normochromic
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some regenerative anemias (horses), FELV induced non regenerative anemia
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microcytic, hypochromic
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iron deficiency. Could be portosystemc shunt (if PCV is normal)
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microcytic, normochromic
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some iron deficiencies, some portsystemic shunts
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hyperchromic
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artifact
|
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which type of polycythemia is most common?
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relative
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results of dehydration
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relative polycythemia, increased total protein. Leukocyte and platelet numbers normal
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erythrocyte redistribution
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cause of relative polycythemia- splenic contraction. (horses/cats)
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which form of absolute polycythemia is most common?
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secondary
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the number of neutrophils in circulation at any point in time represents the balance between:
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production in the marrow and utiliztion in tissues
|
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neutrophils are an important part of the ______
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acute inflammatory process
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lymphocytes of ruminants are usually
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as large as neutrophils
|
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reactive lymphocytes
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have deep blue cytoplasm, more irregular nucleus and indicate antigenic stimulation
|
|
large granular lymphocytes
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have distinct small magenta (azurophilic) granules in their cytoplasm and may represent either t-cells or NK cells
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monocyte appearance
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greyblue cytoplasm, vacuoles, light purple granules. Typically larger than neutrophils. Nucleus can be any shape, but normally bean shaped and less clumped "lacy" chromatin compared to neutrophils
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left shift
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increased concentration of immature neutrophils in blood (bands/metamyelocytes). This can be either: increase in absolute numbers above the reference range OR more than 10% immature cells in a neutropenic animal
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two types of left shift
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regenerative: segmented neutrophils outnumber the immature forms. Degenerative: immature forms outnumber the segmented neutrophils (neutropenia with a left shift)
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toxic change
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morphological change in cytoplasm of neutrophils. Result of accelerated production. Changes include more basophilic cytoplasm, dohle bodies, foamy vacuolation, toxic granulation, giant neutrophiles, and ring-shaped nuclei
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dohle bodies
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grey blue aggreages of endoplasmic reticulum in toxic neutrophils
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hypersegmented neutrophils
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5 or more distinct lobes, associated with aging
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leukemoid response
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extreme leukocytosis/neutrophliia due to inflammation that mimcs granulocytic neoplasia
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myelodysplastic syndrom is considered a ______ state
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pre-leukemic
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where is myelodystplastic syndrome most recognized?
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in felv cats
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are toxic neutrophils and degenerate neutrophils the same thing?
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NO
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degenerate neutrophile
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neutrophils not in peripheral blood (ie, in a cytology specifm). Reflects unhealthy environment often associated with bacterial toxins. Changes include nuclear swelling, cell lysis, etc.
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|
pelger huet anomaly can mimic a
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left shift
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what is the typical result of most inflammatory processes?
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neutrophilia
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presence of a left shift always indicates
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inflammation
|
|
very severe acute inflammation results in
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neutropenia with a left shift
|
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significance of neutropenia with a left shift in domestic animals? In cattle?
|
domestic animals: poor prognostic signs. Cattle- typical response.
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cattle have low ____ reserves and slow ______ capacity
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marrow reserves, proliferation capacity
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how do horses respond to inflammation? What test is also useful in horses to diagnose inflammation?
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respond with neutrophilia without a marked left shift. Fibrinogen concentrtion test
|
|
excitement response
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immediate shift of cells from marginated pool to circulating pool. Effect is mature neutrophliia and lymphocytosis. NO left shift.
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|
rule of thumb for excitement response neutrophilia
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up to 2x the upper reference range is consistent with excitement (3x in cats). More than that is likley chronic inflammation
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|
steroid response-
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shifts lymphocytes from circulation to tissues. Mature neutrophilia and lymphopenia +/- monocytosis. Magnitude of neutrophilia similar to excitement response.
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|
common cause of significant lymphocytosis
|
lymphocytic leukemia (lymphoblastic or chronic lymphocytic)
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what is chronic ehrlichiosis associated with?
|
marked lymphocytosis, with the morphology of LGLs
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what is significant about the LACK of lymphopenia in a sick animal?
|
should consider hypoadrenocorticism
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most common causes of eosinophilia
|
ecto and endo parasites
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what is significant about cat platelets?
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typicall 2x the size of other species (platelets can be counted as RBCs based on size)
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|
the interpeation of bone marrow is directly related to the peripheral blood picture at:
|
the time of the bone marrow sampling
|
|
normal PCV, neutrophlilia, and Left shift. Bone marrow shows increase in the M:E ratio. Could indicate
|
granulocytic hyperplasia present in the marrow
|
|
what is required for adequate interpreation of the bone marrow findings?
|
concurrent CBC
|
|
indications for bone marrow aspirate
|
unexplained cytopenias, potential malignancies involving the marrow, infection infolving the marrow, FUO, radiographic lytic bone lesions, unexplained hypercalcemia
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|
dysproteinemia
|
abnormal concentrations of a normal blood protein
|
|
negative acute phase protein
|
concentration decreases in response to inflammation (ie, albumin)
|
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what affect does inflammation have on fibrinogen in horses and cattle?
|
it increases
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|
which is usually higher: TP from refractometer or from chemistry profile? Why?
|
the refractometer. Usually done on plasma rather than serum, wich lacts fibrinogen and some other coagulation proteins
|
|
why is the margin of error of fibrinogen important?
|
there is no real clinical difference between a fibrinogen of 600 and one of 700 if the margin of error is 200mg/dl.
|
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in animals with bleeding disorders, are you interested in increased or decreased fibrinogen?
|
decraesed
|
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can decreased fibrinogen be detected with a heat precipitation method?
|
no
|
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how can you detect decreased fibrinogen?
|
quantitative method based on thrombin time
|
|
effect of hydration status on albumin
|
dehydration will tend to increase serum albumin concentrations. Overhydration will decrease (globulins are affected to the same degree)
|
|
effect of hepatic synthesis on albumin
|
liver failure (severe) can decrease concentration
|
|
high serum albumin is highly specific for
|
dehydration
|
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effect pf liver disease on total globulin concentration
|
usually not below reference intervals
|
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which immunoglobulins are sometimes found in the beta region?
|
IgA and IgM
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what does a broad, hill-like increase indicate?
|
incraeses in many proteins that are all running together on the gell
|
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what does a small narrow peak indicate?
|
increase in one specific proteins
|
|
why is electrophoresis usually run?
|
to evaluate marked increases in globulin fraction of serum proteins. To differentiate increases in alpha and beta globulins (usually acute phase responses) from incraeses in gamma globulins (chronic inflammation or Ig producing tumors)
|
|
what does the shape of the peak seen with gamma globulins indicate?
|
broad peaks indicate chronic inflammation, narrow peaks (same as or narrower than albumin) indicate immunoglobulin producing tumors
|
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what, besides inflammation, can increase fibrinogen?
|
dehydration- raises F proportioanlly with TP
|
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if fibrinogen is incraesed but does not make up more than 10% of the total progein, what is still possible?
|
acute inflammation, but may be just due to dehydration
|
|
main cause of decraesed fibrinogen
|
DIC
|
|
panhypoproteinemia
|
hypoalbuminemia + hypoglobulinemia
|
|
causes of panhypoproteinemia:
|
overhydration/excessive fluid therapy. Blood loss, protein losing enteropathy, exudative skin lesions, high protein effusions,
|
|
what causes hypoalbuminemia with normal to increased globulins?
|
liver failure, malnutrition, acute/chronic inflammation, glomerular disease
|
|
how can loss of both protein fractions result in hypoalbuminemia with normal to increased globulins?
|
possible that globulin just did not drop enough to leave the reference interval, or the animal started out with an increased globulin concentration (due to inflammation/immune stimulation)
|
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what can cause hypoglobulinemia with normal/incraesed albumin?
|
FPT, decrease in globulins is almost always the result of a lack of immunoglobulins
|
|
what can cause hyperalbuminemia only?
|
dehydration
|
|
what can cause hyperalbuminemia with hyperglobulinemia?
|
dehydration (this is more typical than increased albumin alone)
|
|
what can cause hyperglobulinemia with normal/decreased albumin
|
incraesed production of globulins (acute inflammation, chronic inflammation/immune stimulation, lymphoid neoplasia). Also, dehydration if the animal started out with low albumin due to a selective hypoalbuminemia - ie, glomerular dz or lvier failure
|
|
diseases that typically result in a polyclonal respones?
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ehrlichiosis, leishmaniassis, chronic pyoderma, etc.
|
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what does a monoclonal peak usually signify?
|
a lymphoid neoplasia
|
|
define hemostasis
|
physiologic cessation of bleeding
|
|
why does coagulation only occur with vascular injury?
|
coagulation factors are mostly present in an inactive form. The endothelial cells that line blood vessels passively/actively function to inhibit coagulation.
|
|
true or false: there are always forces both favoring and opposing coagulation actively occuring
|
TRUE
|
|
initial event in hemostasis
|
reflex constriction of local blood vessels
|
|
platelet adhesions
|
the first cellular event, where platelets line up along the injured area
|
|
what activates platelets?
|
adhesion.
|
|
platelet agonists
|
secreted by activated platelets, recruit and activate additional platelets to form an aggregation
|
|
primary hemostasis
|
the process of forming a platelet plug at the site of injury
|
|
what does the platelet plug do?
|
it stops bleeding from very small wounds. It is not very stable. In larger wounds, the blood pressure would disrupt the plug
|
|
soluble coagulation factors
|
a group of proteins produced by the liver that act in sequential order to activate each other (coagulation cascade). Fibrinogen is eventually converted to fibrin at the site of the platelet plug.
|
|
secondary hemostasis
|
the process of coagulation factors producign fibrin to stabliize the platelet plug
|
|
Why is it important to divide coagulation into ‘primary’ and ‘secondary’ hemostasis?
|
The clinical bleeding episodes that you see with defects of primary hemostasis are sometimes different than those seen with defects of secondary hemostasis. Sometimes, you can guess which system is affected from the clinical signs. Also, lab tests usually evaluate either primary or secondary hemostasis. This allows you to quickly determine where the problem is, reducing the number of possible causes
|
|
what does platelet adhesion require?
|
a serum protein called von Willebrand factor
|
|
is von willebrand factor involved in secondary hemostasis?
|
not directly
|
|
vWF is the only protein that can:
|
adequately mediate platelet adhesion in vessels with high sheer force
|
|
thrombocytopenia
|
most common cause of abnormal bleeding
|
|
receptor for vWF
|
platelet glycoprotein 1b
|
|
receptor for fibrinogen
|
glycoprotein IIb/IIIa
|
|
important biochemical pathway required for normal platelet function
|
arachadonic acid metabolism that results in the production of thromboxane A2 (TXA2).
|
|
The major things needed for primary hemostasis to occur normally
|
(1) adequate numbers of platelets, (2) normal platelet function, and (3) von Willebrand factor. These are your differentials for a defect in primary hemostasis.
|
|
arrangement of the coagulation cascade
|
two arms: intrinsic and extrinsic systems that terminate in a common pathway
|
|
factors involved in intrinsic pathway
|
XII, XI, IX, VIII
|
|
factors involved in extrinsic pathway
|
VII
|
|
factors involved in common pathway
|
X, V, II, I
|
|
**What are the vitamin K dependent factors**
|
II, VII, IX, and X KNOW THESE!!
|
|
which factor has the shortest half life (and would become depleted first if vitamin K antagonists were ingested)
|
VII
|
|
when faced with a bleeding animal you need to first determine
|
if it is a hemostatic defect vs trauma/disease induced hemorhate
|
|
signs assocated with defects in primary hemostasis
|
petechial hemorrage (usually with TCP), bleeding from mucosal surfaces, slow prolonged oozing of blood
|
|
signs assocated with defects in secondary hemostasis
|
large hematoma formation, bleeding into body cavities, frank hemorrhage
|
|
BMBT
|
buccal mucosal bleeding time
|
|
BMBT-
|
measures the amount of time it takes to stop bleeding from a small, standardized stab incision. Usually less than 3.5 minutes. Not a very sensitive test.
|
|
some animals with a primary hemostatic defect will have a normal
|
BMBT
|
|
most common cause of abnormal bleeding of any kind
|
TCP
|
|
most common cause of low platelet count in cats?
|
artifact due to platelet clumping
|
|
macrothrombocytopenia
|
cavalier king charles, abnormally large platelets. Asymptomatic, usually no clinical bleeding episodes
|
|
automated platelet counts are frequently
|
inaccurate
|
|
most common of the inherited bleeding disorders
|
von willebrand dz
|
|
platelet function defects can be ___ or ___
|
inherited or acquired
|
|
tests of secondary hemostasis include
|
activated clotting time, activated partial thromboplastin time (PTT), one stage prothrombin time (PT), specific factor analysis, fibrinogen degragation products & d-dimers
|
|
what two tests are usually run on the same sample?
|
PT/PTT
|
|
what must occur for either PT or PTT to be prlonged?
|
the concentration of one or more of the coagulation factors tested must be below about 30% of normal (i.e., they must be markedly reduced before the tests will be abnormal).
|
|
what happens if you underfill the citrate tube?
|
, there will be a relative excess of anticoagulant (ie, the same amount of citrate is in the tube but it is being diluted in less blood). This can result in artificial prolongation of the PT/PTT.
|
|
if PT and PTT are both prolonged, what assumptions can you make?
|
there is a defect in the common pathway OR multiple factors are being affected (both intrinsic and extrinsic are affected)
|
|
why are finbrogen degregation products and D-dimers run along with Pt/PTT?
|
to test for DIC or other thromboembolic dz
|
|
rickettsial diseases
|
ehrliciosis, RMSF, etc. causes TCP, animals may present with petechia or mucosal hemorrhage. TCP may be severe. In chronic form of the dz, will see pancytopenia. Diagnose via antibody titers or PCR
|
|
ITP
|
immune mediated thrombocytopenia: can be idiopathic or secondary. Usually a diagnosis of exclusion.
|
|
DIC
|
disease starts out with excessive coagulation and thrombosis occurring, eventually the animal has bleeding symptoms because of the depletion of platelets and coagulation factors. Because of this, DIC is sometimes called a ‘consumptive coagulopathy’
|
|
is DIC a disease?
|
no, it is a manifestation or end result of other disorders.
|
|
effects of DIC on coag test?
|
prolongagions of PT, PTT, ACT + increased concentrations of D-dimers or FDPs
|
|
True or false: the liver can produce coag factors faster than the bone marrow can make platelets
|
TRUE
|
|
what blood smear finding will help support DIC?
|
schistocytes
|
|
how does bone marrow result in TCP
|
lack of platelet production
|
|
myelophthisis
|
crowding out of normal bone marrow tissue by an abnormal cell type. Commonly myelofibrosis
|
|
how many forms of von willebrand dz are there?
|
three
|
|
animals with vWd generally only bleed if
|
the vWf concentration is below 30% of normal
|
|
what is the most common coagulopathy affecting the coagulation proteins
|
vitamin K antagonism
|
|
most common source of vit K antagonism
|
poisons / rat poison (warfarin like molecules)
|
|
what will happen to mycoplasma hemoparasites in EDTA?
|
they will fall off
|
|
appropriate bone marrow responses: the lower the PCV,
|
the higher the percentage of retics required to consider the anemia regenerative
|
|
why may TP be normal with chronic hemorrhage?
|
liver synthesis will keep up with the blood loss
|
|
will you see hypochromasia on a blood film even if MCHC is normal?
|
yes- MCHC is an average
|
|
is iron defiiency anemia regenerative?
|
yes, it starts off that way, but becomes non regenerative as iron stores are depleted
|
|
macrocytosis causes
|
reticulocytosis, agglutination, hereditary (poodles), breed (normal greyhounds), felv induced dysplasia
|
|
what will a coombs test induce?
|
agglutination if there is antibody bound to RBCs
|
|
describe an echinocyte
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short, evenly spaced spicules
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descreibe an acanthocyte
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blunt, unevenly distributed spicules
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Dog has increased WBC count, neutrophilia, increased bands, lymphopenia, monocytosis. Hemopathology is normal. What kind of response is this?
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inflammatio and stress
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Horse has increased WBC count, neutrophilia, lympocytosis.
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excitement response
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horse is leukopenic- neutropenic. Metamyelocytes are present. Lymphopenia. Smear shows markedly toxic neuts
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inflammatory stimulus + stress, with a left shift
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mild leukocytosis, lymphocytosis, lymphs are LGLs
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could be leukemia or ehrlichia
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will acute lymphocytic leukemia show normal morphology?
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no
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what kind of morphology will chronic lymphocytic leukemia show?
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normal or LGL
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Leukocytisis, neutropenia, lymphocytosis, circulating blasts, hemopath shows lg immature lymphs.
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acute leukemia
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