Exam 1 Clin Path Flashcards
Reticulocytes What are they? Why do we count them?
What are they? –Immature RBC that have lost their nuculus but still contain organelles. –These organelles clump and form reticulums that appear as blue clumps Why do we care? –to determine if the anemia is regenerative or not
3 main things that cause anemia
- blood loss (usually see with decrease in Total protein) 2. blood destruction 3. insufficient production by bone marrow (will NOT see increase reticulocytes)
What is a leukogram?
part of a CBC that refers to leukocytes
Decreased lymphocytes is almost always associated with?
STRESS The endogenous cortisol release due to the stress of an animal being sick is cytotoxic to lymphocytes
What are some problems with machine leukogram counts?
–Cannot distinguish b/w nucleated RBC and WBC and thus NCC may be inaccurate –Cannot distinguish between band and mature neutrophils
What does an increase in band neutrophils suggest?
Inflammation!
What is the most common cause of Heinz Body formation in cats? What are other causes?
Acetaminophen (Tylenol)
Others:
Propylene Glycol (rare- but they used to put it in chapstick and cat food to soften it)
Ketosis- ketones cause oxidation of hemoglobun
What is that on this RBC?
Heinz body
What are Heinz bodies? and How do they cause anemia? What species is most susceptible?
Heinz bodies are composed of:
denatured hemoglobin
How do they cause anemia:
(1) decrease membrane flexibility –> more susceptible to breaking, especially in smaller capillaries
(2) change in RBC antigenicity –>
(a) destruction by macrophages
(b) antibody-antigen complex formation –> complement activation –> MAC –> intravasular lysis
Most susceptible species: Cats
Why do you see low Phosphorus when you have PU/PD and diabetes?
Phosphorus is removed via urine
Glucose causes osmotic diuresis and phosphorus is drawn out with the water
Why is the main cause of increased albumin?
Dehydration
What level does Total Bilirubin have to reach before the patient is “yellow”/incteric ?
Normal range is about 0- 0.3
2- 2.5 or higher
Increase T bili is caused by (1) increased RBC destruction (2) Liver dysfunction (3) bile duct obstruction
What are some unmeasurable anions that increase the anion gap?
Ketones and Lactic acid
What do you see in blood work of a cat when it is excited? vs stressed?
Excited: increase in epinephrine
- increase in glucose as high as 450 mg/dL
- INCREASE in lymphocyte count (up to 20,000 in CATS only)
Stressed: increased cortisol
- mild increase in glucose
- lymphoPENIA
What does the Mean Cell Volume (MCV) measure?
Average size of the RBC
Low MCV is the hallmark of iron defiiency anemia
Mean Corpuscular Hemoglobin Concentration (MCHC)
Measures average Hg concentration in RBC
Useful in determining type of anemia
RDW
Distribution width of the rbc
calulated erythrocte indices
What would you see in Spenic hemangiosarcoma?
Common in old large breed dogs
Mass may rupture and generate a hemoabdomen–> anemia
If tumor seals over- the blood in the abdominal cavity is reabsorbed (protein and iron will be recycled)
See acanthocytes (RBC with projections) and schistocytes (fragmented RBC)
Confirm via aspirating abdominal fluid -or- U/S for mass
Blood loss indications- regenerative anemia (high retics & nucleated RBC), decrease Total Protein (may reabsorb and look normal), decrease platelets (consumption)
may see cortisol/stress induce decrease lymphocytes
Immune Mediated Hemolytic Anemia
Most common cause of blood destruction anemia in dogs
Spherocytes! - ball shaped RBC due to the loss of plasma membrane while maintaining Hg concentrations
90% of dogs with IMHA have inflammatory leukograms (high band neutrophils and leukocytosis)- possibly due to necrosis associated with anemia or DIC or macrophage activation
May be accompanied by immune-mediated thrombocytopenia= Evans syndrome
Treatment: glucocorticosteroids to calm the immune system
Evans Syndrome
Combo of IMHA and immune mediated thrombocytopenia
Iron deficiency anemia
LOW MVC is hallmark- RBC belive to be smaller due to extra divisions
In nursing animals due to the low concentrations of iron in milk. This is quickly corrected once the animal is placed on a solid diet that is rich in iron.
In adult animals iron deficiency is due to either:
(1) decrease absorption
(2) Increase loss- such as in chronic blood loss (ie parasitic infetion)
What are some things that only affect RBC production?
Ie if you have non-regenerative anemia
Usually external things
(1) Inflammaion= anemia of inflammatory disease (AIDs)=most common cause of non-regenerative anemia in domestic animals but is not very clinically significant because it corrects itself once the inflammation is removed and is not very severe. This will also have INCREASED storage iron and normocytic in most domestic animals (low MCV in humans)
Why would you see a higher PCV?
high elevation (in colorodo)
How early will you see reticulocytes after blood loss/ blood destruction?
24 hours
What are some things that cause generalized bone marrow production problems
- Chronic Ehrlichiosis –> pancytopenia by affecting bone marrow stem cells
- chemicals
- drugs
- immune mediated disease
What is the Packed Cell Volume? vs Hematocrit?
Percentage of whole blood composed of erythrocytes
Called “hematocrit” when calculated by instrument
What is within the Buffy Coat?
Leukocytes
• Nucleated erythrocytes
• Platelets
What are two causes of yellow plasma?
- Icterus
- Carotene pigments- associated with diet in large animals
What causes White/Opaque Plasma? Why is this a problem? and how do you avoid it?
lipemia (chylomicrons)
may be due to postprandial collection or diseases associated with abnormalities in lipid metabolism (ex. diabetes)
Interferes with biochemical profile reading
restrict food for 12 hours before blood is drawn
What makes plasma red?
What are two causes? how do you tell the causes apart?
Red discoloration is due to the presence of hemoglobin in plasma due to hemolysis
Causes:
(1) in vitro technique -destruction during sample collection
(2) Lipemia- induces RBC lysis in-vitro
(3) In- VIVO hemolytic anemia due to intravascular hemolysis
How do you tell them apart? normal PCV=in-vitro, decreased= in-vivo
Plasma protein by refractometry
Refractometers estimate the concentration of solute in fluid, since solute bends slight passing through the fluid proportionate to the solute concentration.
Assumes all solutes are proteins.
Serem T protein will be lower than plasma Total protein due to fibrinogen.
What is the difference b/w Serum and Plasma?
SERUM- NO anticoagulant in collection tube, thus coagulation proteins (fibrinogen) are not in fluid because they are in the blood clot
PLASMA- collected in EDTA tube - keeps coagulation protein within the fluid.
Plasma will have a slighly higher total protein than serum.
What artificially increases the estimate of plasma proteins by refactometry?
Lipemia
Urea
Glucose
Cholesterol
Plasma will be higher than serum due to plasma still containing coagulation factors
Total Leukocyte Concentration/ Total nucleated cell count
Detects all nuclei in solution in which the RBC have been removed by lysis
“Leukogram”
includes nucleated RBC in count if done mechanically
Used to CALCULATE the specific leukocyte types
Differential nucleated cell count
Classifies nucleated cells as:
Segmented neutrophils
Band neutrophils
Lymphocytes
Monocytes
Eosinophils
Basophils
Nucleated RBCs
How do you convert % of each cell to absolute number?
ON EXAM
Multiply the total nucleated cell concentration by the percentage of each leukocyte type to yield the absolute concentration of each type of nucleated cell within the blood sample.
Eg, total nucleated cell count = 10,000 μl
80% of cells are segmented neutrophils
80% x 10,000 μl = 8,000 μl segs
What is a Macroplatelet?
young platelet that approaches the size of RBC
aka giant pletelet
How many platelets should you see per oil immersion field?
6-10
Where should you look for clumped platelets on a blood film? What is the side effect of having high clumping?
Which species often has this?
Look for clumped platelets on the feathered edge
Clumping of platelets will make your platelet count erroneously low.
80% of cats have platelets that clump quickly
What doyou get with your automated hematologic instrumentation?
What are some problems?
Cell particle counting and sizing
• RBC count (x106/μl
• MCV (fl)
• Nucleated cell count (μl)
• Differential cell count (μl) - does not count neoplastic cells and does not recognize band neutrophils
• Platelet count (μl)
• Reticulocyte count and size (μl, fl)
Spectrophotometry
• Hemoglobin concentration (g/dl) (usually approx
1/3 of the PCV)
What should the Hemoglobin concentration be compared to the PCV? (disregarding units)
Hemoglobin concentration is usually approx
1/3 of the PCV
How do you calculate the Hematocrit on automated instruments?
(MCV x RBC)/10 = HCT (PCV)
should match the manual PCV- if not there is an issue with MCV measurement or RBC count
How would you calculate MCV manually?
PCV/RBC x 10 = MCV
not done anymore. High errror
How do you calculate the MCHC?
[Hgb (g/dl) / PCV (%)] x 100 = MCHC (g/dl)
normally b/w 32 to 36 g/dl in all species EXCEPT camelids which are approx. 41-45 g/dl
What approxamatly is the normal MCHC?
32 -36 g/dl in all species EXCEPT camelids which are approx. 41-45 g/dl
What causes an increase in MCHC?
ARTIFACT!!!
Due to hemolysis, lipemia, or presence of
Heinz bodies (pieces of denatured hemoglobin as
a result of oxidation will break off and look more dense and interfere with reading).
RBC can only contain so much Hg, so it cannot naturally be high
Also be due to incorrect PCV
What causes a decrease in MCHC?
(1) SEVERE iron deficency (does not always happen in animals)
(2) presence of many
reticulocytes that are still making hemoglobin,
usually associated with a regenerative anemia. Reticulocytes have the same Hg but they have more membrane and thus the concentration is lower.
Size distribution curve
Established for each population of cells
(eg, leukocytes, erythrocytes, platelets).
Should be bell shaped curve
Species specific, thus sizing has to be adjusted for species
MCV of RBC?
Dogs, cats, horses, cows. sheep, llama, goats, humans?
Dog: 60 - 72 fl - central pallor
Cat, horse, cow: 39 - 52 fl
Sheep: 25-35 fl
Llama: 21 - 29
Goat: 15-25
Human: 80 - 100 fl - central pallor
Red cell distribution width (RDW)
Why would the curve be wider?
Describes the relative width describes the relative width of the size distribution curve.
• It is the standard deviation of most of the erythrocytes divided by the MCV.
The tails of the erythrocyte distribution are usually excluded from this calculation.
Why would you have a wider curve?
(1) abnormal number of big cells (2) abnormal number of small cells (3) both (two cell populations)
Why would you have two population of RBC?
- recovering from iron deficiency anemia -or- recovered from chronic blood loss
- blood transfusion
- -mixing of dog and cat blood together…
Polychromatic RBC
Reticulocytes are polychromatic RBCs when stained with Wrights stain
Look slightly blue but not clumping
Reticulocyte concentration
Determined by Flow technology or manually (with special stain)
Immature erythrocytes (reticulocytes) still have organelles for protein synthesis and aerobic metabolism (ribosomes and mitochondria). Certain stains cause these residual organelles to aggregate, resulting in clumped material that can be seen.
Do not bother to manually count the reticulocytes unless the dog has less than 30 PCV, and a cat with PCV less than 24
Reticulocyte count
Use New Methylene Blue or Brilliant cresyl blue to see clumped organelles
Multiply the % reticulocytes (from counting 1000 RBC) by the total RBC count to obtain an absolute reticulocyte concentration
What are normal reticulocyte concentration in dogs, cats, cows and horses?
Dogs: 0 - 60,000/μl
Cats: 0 - 40,000/μl
Cows: 0, but release when regenerative anemia
Horses: Do not release reticulocytes
You have an anemic horse, should you order a reticulocyte count to determine if it is regenerative or not?
NO!!!!!!!!
They dont even release reticulocytes, silly!
What can you say about these reticulocyte ranges?
0 - 10,000μl
10,000 - 60,000 μl
60,000-200,000 μl
> 200,000 μl
Non regenerative anemia: 0 - 10,000μl
Poorly regenerative anemia: 10,000 - 60,000 μl
Mild to moderate regeneration: 60,000-200,000 μl
Maximal regeneration: > 200,000 μl
So, tell me about reticulocyte maturation in dogs and cats?
Dogs - 24 -48 hours from release to maturation
Cats - Aggregate reticulocytes become punctate reticulocytes. Punctate forms are not polychromatophilic with Wrights stain, and are not counted in the reticulocyte count. Aggregates become punctates in approx 12 hours. Punctates persist for 12 days
What is a punctate reticulocytes? What species has it? When do they form? and how long do they persist?
>^CATS^
Aggregate reticulocytes become punctate reticulocytes.
Punctate forms are not polychromatophilic with Wrights stain, and are not counted in the reticulocyte count.
Aggregates become punctates in approx 12 hours.
Punctates persist for 12 days
What does it mean is ALL of your cats RBC are punctate reticulocytes?
All your RBC are less than 12 days old (RBC lives about 70 days in cat)
Cat must be recovering from blood destruction or blood loss
(Ex. Cat is recovering from heinz body anemia!)
What is your MCV in regenerative anemia?
High!!
Macrocytic anemia- regenerative
In domestic animals, what kind of anemia do you have with Viramin B deficiency?
Normocytic Anemia!
What is a cause of microcytic anemia? what is your MCV?
Iron (Fe) deficiency anemia
LOW MCV!!
True or False:
You should ignore the feathered edge of a blood film
FALSE!!
You should always scan it to look for platelet clumps or other large things such as microfilaria
What are common causes of polychromasia?
Blood loss
Blood destriction
Recovering marrow (least common)
Which species will have hypochromasia in iron deficiency anemia?
Dogs and Llamas
Llamas will also have a thin membrane and folded RBC
Cats DO NOT get pale, if they do it is very subtle
How would you describe this?
Why would this happen?
“Punched out” or “Bowl” shaped RBC
NOT a true hypochromasia. Rim of RBC is wider and darker than a true hypochromasia
Happens due to a membrane disorder/defect in which the RBC do not “bounce back” after going through small cappilaries
What are Acanthocytes, Echinocytes and Keratocytes all classified as?
Spiculated RBC
They all have projection from their membrane
What are the arrows pointing to? What is this indication of?
Acanthocytes!!
They have few, unevenly distributed projection (usually larger than Echinocytes) due to changes in lipid concentration in the RBC membrane
Indicates:
Humans with liver disease
Cats with hepatic lipidosis
Dogs with any hemangiosarcoma (20% of the time)
Also just been seen in dogs in St. Kitts
What are these? What are they called when they are formed in-vitro? Why do they form in-vivo?
Echinocytes!!
They have numerous, short spicules about the same shape. Does NOT affect polychromatic cells.
In-vitro= crenation = form due to pH changes during slow drying of film. Common in humid areas!
In-vivo formation:
- Electrolyte imbalances (eg. calve with diarrhea)
- Non-specific diseases (eg, kidney disease due to increase netrogenous waste)
- Rattlesnake envenomation= Type 3 echinocytes= diagnostic!!
What will you see on a blood film of a dogs with Rattlesnake envenomation?
Type 3 Echinocytes with small needle like projections
Loss of central palor
Polychromatic cells are not affected
What cells wont have echinocyte formation?
polychromatic cells!
What are some causes of Schistocytes?
-
Intravascular trauma (eg, DIC, vascular tumors)
- If DIC, platelet count will be low
- DIC causes fragmentation due to RBC being clothes-lined to fibrin strands of clots
- Iron Deficiency Anemia - fragmentation is secondary to shape change and membrane abnormalities
What does the presence Spherocytes suggest?
IMHA!!!
Spherocytes are Erythrocytes that appear small and lack central
pallor. But the volume is normal.
What is a Spherocyte?
Spherocytes are Erythrocytes that appear small and lack central
pallor. But the volume is normal.
Presence suggests IMHA
What are the arrows pointing to? What our some nick names? When are these most commonly seen?
Keratocyte
RBC abnormality in which you have one ot two long spicules that form due to the fomration of a “bubble” within the membrane
May be called apple stem cells or purse cells
Seen in Iron deficincy anemia
Other things to notice with picture: Cats do not lose their central palor with iron deficiency anemia (unlike dogs). There are macroplatelets (50% of iron deficiency anemia also has thrombocytosis- possibly due to megakaryocyte response to EPO)
Which species has a marked central palor increase with iron deficency anemia?
DOGs
What are the arrows pointing to?
Describe them! What does it suggest? How are they formed?
Spherocytes!
RBC that appear small and lack central pallor. Volume is normal (MCV is normal)
Presence suggest IMHA
Formed by macrophages nibbling off peices of membrane due to Ab-Ag complexes and complement attachment.
Amount of Hg within the cell is the same, there is just less membrane so the cell becomes a “beach ball” instead of a biconcaved “frisbee”
May also see evidence of regeneration and agglutination (if IgM).
Difficult to see in cats, horses and cows due to their lack of central pallor and already small RBC. Good thing IMHA is most common in dogs!!
What are some things that can cause IMHA? What will you see?
IMHA can be caused by viruses, haptens, drugs, heinz bodies that cause changes in antigenicity, intracellular parasites.
See sphirocytes!
Also regeneration, normal MCV.
In addition to sphirocytes, what also can cause RBC to look smaller?
Aging
This may be the cause of smaller looking RBC if there are very few present.
What type of antibody cause agglitination of RBC?
IgM
What is is called when an entire RBC is phagocytosed by a macrophage? Where does this usually occur?
Extracellular hemolysis
Occurs in the sinosoids of the spleen.
When does intravascular hemolysis occur?
Occurs when there is high Ab-Ag complex formation or high complement activation that leads to completion of the complement cascade with a MAC complex
The pores formed by the MAC complex cause spilling of hemoglobin into the blood, and subsequently the urine.
Patients with intravascular hemolysis may also have increased bilirubin levels due to incread RBC destruction (Pre-hepatic cause of icterus)
What is the arrow pointing to? What is the most common cause of this in dogs?
Eccentrocytes - shifting of hemoglobin to one side of the cell that results in a clear zone outlined by membrane.
Caused by oxidative damages to hemoglobin.
Ingestion of Onions is the most common cause of eccentrocytes in dogs.
Often seen in conjunction with Heinz body formation.
What is a torocyte?
bowl-shaped erythrocyte
Do not mistake for hypochromasia cells
Occurs due to membrane abnormality that causes the cells not to bounce back after shape change while passing through small capillaries
What is a leptocyte?
Leptocytes are thin RBC
Not diagnostic/clinically significant
Sometimes caused by iron deficienct anemia
What are the arrows pointing too? Is it diagnostic for anything?
Target Cells
Target cells are RBC that have a “glob” of dense hemoglobin within the area of their central pallor.
Not signifigant- it is not diagnostic for anything
Sometimes seen in animals with high cholesterol, but also seen in normal animals so, again, not significant
What are these RBC called? Which breeds are predisposed? Our they significant?
Stomatocytes
Very rare RBC morphology change in which the central pallor is wide and narrow and looks like a mouth.
Not significant, especially if very few are present.
If abaundant, it due to genetetic predisposition
Common in:
Dwarf Alaskan Malamutes
Miniature Schnauzers (normal)
Drentse partrijshond (with inherited GI disorder)
What are 6 causes of Heinz Body Anemia in small animals? Which species are each of them in?
- *ACETAMINOPHEN** (CATS)
- *PROPYLENE GLYCOL** (CATS)
- *ILLNESS** (CATS)- lymphoma, hyperthyroidism, diabetes= ketotic
- *ONIONS** (ALL SPECIES), garlic powder
- *CEPHALOSPORINS** (DOGS)
- *Zinc toxicosis** (penny ingestion)- cause fatal anemia in puppies
Use New methlene blue stain to see (always preform if anemic cat). Often not obvious on wright stain.
What are causes of heinz bodies in horses, cattle and sheep?
Horses:
Phenothiazine
Wilted red maple leaves** Most common**
Cattle:
Kale
Onions
Sheep:
Copper toxicosis- will store Copper in liver and then release it when stressed
Basophilic stippling
What is it? when does it occur?
Basophilic stippling are abnormal aggregation of ribosomes that form in-vivo and appear a small basophilic granules with a simple wright stain.
NORMAL in ruminats- especially within polychromatophilic cells
Small animals may have them if very regenerative anemia or lead poisening
Lead poisoning also has neuro and GI signs.
What are four causes of Nucleated RBCs/ Howell Jolly Bodies
4 causes:
(1) Regnerative anemia
(2) Non-functional spleen or splenectomy - loss/decrease of macrophages to uptake nucleated RBC
(3) Increased corticosteroids - endogenous or exogenous - inhibit macrophage function
(4) Lead poisening
What are blood indications that you should check lead levels for lead poisening?
Basophilic Stippling
Nucleated RBC/ Howell-Jolly bodies
Where will you find distemper inclusion bodies? What do they look like?
Distempter inclusion bodies are within erythrocytes and leukocytes
They are rare and only present in the early stages of the disease (not good for diagnosis)
The color depend on the stain you are using
What is this RBC arrangement? When does it occur? What is a way to differentiate it?
Rouleaux formation
Normal in horses
Suggests increased globulin in small animals
To differentiate, add isotonic saline to drop of blood.
If rouleaux, disperses. If agglutination, persists.
May look clumped if severe.
How do you differentiate agglutination from Rouleaux formation?
Add isotonic saline to drop of blood.
If rouleaux, disperses. If agglutination, persists.
What does agglutination suggest?
IgM attachment to RBC (IMHA)
What are some obvious clinical sign differences of patients with acute anemia disorders, compaired to those with chronic anemia disorders?
Patients with acute anemia disroders will be weak at a higher PCV.
Patients with chronic anemia disorders have had time to compensate and still will be walking into the clinic at very low PCV.
Cats can ahve PCV as low as 6% and still appear healthy.
After preforming a protein electrophoresis, what does monoclonal gammopathy suggest?
Monoclonal gammopathy= Neoplasm of plasma cell or B-cell
After preforming a protein electrophoresis, what does polyclonal gammopathy suggest?
polyclonal gammopathy= infection (non-
What are three ways to measure Red Cell Mass
Hematocrit - calculated
PCV- # 1 if manual
hemoglobin concentration - direcly measured
What are clincial signs of anemia? What are things that can be associated with it?
Pale mucous membranes
Lethargy, reduced exercise tolerance
Increased respiratory rate, dyspnea
Increased heart rate
Murmurs if
Polyuris and Polydypsia (In renal failure, also low EPO)
Splenomegaly (blood destruction)
Icterus (blood destruction)
Hemoglobinuria (blood destruction)
Why is splenomegaly associated with blood destruction anemia?
(1) M0 in the spleen uptake RBC
(2) Spleen is an organ of RBC production, if anemia is severe
When trying to diagnose anemia, what are the top 4 test to look at?
Red blood cell mass (PCV)
Mean cell volume
Reticulocyte count (except in horses)
Total protein (usually only in acute blood loss)
What is a cytogram?
dot graph
Large cells are on top
Hypochrome cells to the left
What could your cat have if it has (1) hypochromic cells and (2) low reticulocyte count?
FeLV
you should do further diagnostic tests to confirm
What could cause periodic episodes of weakness in a large breed dog?
Hemangiosarcoma
Also see acanthocyes and schistocytes.
If rupture, you may see acanthocytes in hemoabdomen fluid.
When do you see anemia and PU/PD?
Renal Failure
The kidney produced EPO, which is essential for RBC formation
What will you see in your blood work in acute blood loss?
(1) Decrease total protein (return to normal in one week, maybe faster if internal blood loss)
(2) Decrease PCV
(3) Normal erthrocyte morphology (Except in hemangiosarcoma- 25% will have acanthocytes and schistocytes)
What are examples of acute blood loss (name 5)
TRAUMA
SURGERY
COAGULATION DISORDERS
BLEEDING TUMORS
THROMBOCYTOPENIA (if
** Blood loss does not cause thrombocytopenia- it will maybe only bring platelets down to 90,000 to 100,000**
What are common examples of chronic blood loss?
GI Ulcers, Bleeding GI tumors = LOSS VIA THE INTESTINES IS MOST COMMON
Blood consuming parasites (hookworms)
–
Less commonly- blood in urine, epistasis
What are the most common causes of iron deficiency anemia in young and adult animals?
young= Physiological anemia= due to inadequate iron in milk (may have failure to thrive)
adults = chronic blood loss
Also could be due to malabsorption of iron, cooper deficiency in large animals, peridoxine in large animals
What do you see in Iron deficiency anemia? (13 things..)
- Microcytosis = GOLD STANDARD
- Low PCV
- Low Reticulocyte MCV (only thing that causes this)
- Increased RDW (unless chronic)
- normal MCHC (unlike humans)
- Keratocyte and decreased central pallor on blood film
- Regenerative (unless AIDs or all iron stores depleted)
- Thrombocytosis (may be as large as RBC)
- Decreased Serum iron concentrations
- decrease transferring saturation
- decrease storage iron (ferritin or hemosiderin)
- Normal total iron binding capacity in cats and dogs (increased in other species)- determines how much transferrin the animals liver is making, most animals (other than cats and dogs) compensate for iron deficiency by increasing ferritin.
- Folding RBC (in llamas)
Should you give a adult dog iron supplements to corrects its iron deficiency anemia?
NO!!
Unless the dog is starving, commercial dog food is very very high in iron (to a point where all iron receptors are saturated in the gut) so iron supplements would be useless
YOU SHOULD LOOK FOR THE CAUSE OF BLOOD LOSS
Why is is better to give injectable iron to neonates?
oral iron can be toxic to immature livers
What are differential diagnosis for mictocytosis?
- Iron deficiency anemia
- portosystemic shunts (young animals)
- breed predisposition (asian breeds)
-
anemia of inflammatory disease (decreased MCV with AID common in humans, rare in dogs).
- Usually normocytic in dogs.
- Can differentiate, because anemia of inflammatory disease will have increased storage iron.
If you have a very high reticulocyte count, what would you expect your MCV to be?
Slightly raised. Reticulocytes are larger than normal RBC and may alter your measurement.
Would bleeding into the abdominal cavity cause Iron deficiency anemia?
Nope, the blood (and its iron) is reabsorbed
What are two reasons you would have an increase in nucleated RBC?
Regenerative anemia
Spleen dysfunction
Solutes that will interfere (artificially ↑ TP):
‒Lipemia: chylomicrons, lipids
‒Urea
‒Glucose
‒Cholesterol
If the PCV and TP are proportionally increased, then the patient is….
dehydrated
If the PCV and TP are proportionally decreased, then the patient has….
blood loss
2 major constituents of the “total protein”?
1) Albumin (ALB)
2) Globulin (GLOB)
How can you tell if an increased total protein is due to dehydration or inflammation/neoplasia?
↑ALB and↑ GLOB (dehydration)
↑GLOB (inflammation, neoplasia)
How can you use ALB and GLOB to determine what causes a decreased TP?
↓ALB and ↓GLOB =blood loss, PLE
↓ALB =PLN, liver failure, vasculitis)
↓GLOB =FPT, SCIDS)
What do you usually/routinely stain blood films with?
Wright Stain
Wright-Giemsa Stain
Modified Wright Stains = “Diff-Quick”
What should you do if you have to do a blood film for an anemic patient?
Increase angle
What are signs of toxic change?
Basophilia
Foamy cytoplasm (soap bubbles)
Döhle bodies
Red top tube
no anticoagulant
Blood is expected to clot
Serum used for biochemical profile and many other tests
Red/Black top tube
” Tiger-top, Marble-top”
Serum separator
Gel that promotes blood clot formation and separates cells from serum
Uses:
‒Chemistry analysis
‒Serology
‒Not recommended for drug levels, hormones, or toxin analysis
purple top tube
Ethlenediaminetetraaceticacid (EDTA) with a K+ salt
Anticoagulant, Ca2+ chelator (acts on platelets)
Preserves cell morphology
Uses:
‒CBC
‒Fibrinogen
‒Reticulocyte count
‒Buffy coat analysis
‒Fluid analysis
‒Blood banks
‒Coombs test
‒PCR
‒Endogenous ACTH
What is wrong if you have extremly/non-compatible with life K levels and decreased Ca2+ levels?
Cross contamination of EDTA!
EDTA contains K+ salt and calcium chelators!
******KNOW THIS*****
Green top tube
Heparin!
Heparin is an anticoagulant, inhibits thrombin
Contains fibrinogen
Uses:
‒Chemistry panels
‒Avian/reptile CBC and chemistry panel
‒Plasma colloid oncotic pressure (COPs)
‒Measurement of electrolytes
‒Specific tests (i.e. lead conc, ammonia)
Blue top tube
Citrate
Anticoagulant, Ca2+ chelator
Uses:
‒Coagulation tests: PT, aPTT, FDP
‒PIVKA
‒Antithrombin
‒Coagulation factor analysis
‒Von Willebrand’s Factor analysis
Grey top tube
sodium fluoride oxalate
Contains Anticoagulant, Ca2+ chelator
Inhibits glucose metabolism b/c fluoride inhibits glycolysis
Uses:
‒Plasma for serial glucose, lactate and pyruvate
How much blood do you typically need or CBC and biochemical profiles?
~5 ml
varies by analyzer and pediatric tubes are available
What happens to your blood if you have tissue contamination or traumatic phlebotomy ?
Platelet activation!
‒clot formation
‒erroneously low platelet count (and WBC)
What size needle should you ideally use for filling blood tubes?
Use a 20 G needle or larger for filling.
Don’t force blood into tube
Tubes are vacuum tubes -can utilize the vacuum or can actually take the stopper off and fill.
If using syringe to collect blood and then filling tubes
- work quickly
- Fill tubes that contain anticoagulant first
In vaccum tubes, how do you know how much blood to put in?
Ratio of blood to anticoagulant is designed to be appropriate by amount of vacuum.
What happens if you do not put enough blood into a purple top tube?
excess EDTA –>erythrocytes shrink (due to salts)
‒erroneous decrease in PCV
‒erroneous decrease in MCV
When should you analyze your blood for CBC?
Analyze within one hour- or - Make blood film and refrigerate tube.
Should you refrigerate blood films?
NOOOOO!!
Do not refrigerate blood film, condensation causes cells lysis.
Should you freeze your blood sample for a CBC?
NOOO!!
Do not freeze the sample; freezing causes cell lysis.
What happens if you let blood set for 24 hours at room temperature?
erythrocytes swell, resulting in increase in MCV.
How long should you allow blood to clot for a biochemical profile? What happens if you wait too long?
15 to 30 minutes
Too long= lowers glucose
What is the most likely cause of this bump in a cocker spaniel with IMHA?
Agglutination of RBC
Cat
What are the arrows pointing on the left? the right?
Left= Mycoplasma haemofelis
Right= Water Artifact- spects will be refractile. Occurs when you do not fully dry the slide
Mycoplasma haemofelis
Transmission? Diagnosis? Clinical Signs? Therapy?
Mycoplasma haemofelis = Common, serious cause of severe anemia
Transmitted through (1) infected blood by blood feeding arthropods, (2) **cat bites **, and (3) iatrogenic exposure/blood transfusions (4) vertically
Diagnosis: blood film exam (parasitemia intermittent) or PCR.
Clinical Signs: anemia, splenomegly, fever, lethargy, sometimes icterus. Regenerative (unless underlysing disease -FeLV- or inflammation)
- Usually associated with concurret disease (FeLV, FIV) or predisposing condition (immunosuppression, splenectomy, cat bite abcess)
Therapy- blood transfusion, +/- prednisone to supress RBC destruction, Doxycycline/Enrofloxacin.
- CATS LIKELY REMAIN CARRIERS after treatment.
Dog
Mycoplasma haemocanis
Opportunist, usually only in splenectomized or severely immunosuppressed dogs.
Clinical signs anemia, may look like IMHA, icterus occasionally
Treat with doxycycline
VERY VERY RARE
Bovine. What are the arrows pointing to?
Who is susceptible? What are the clinical signs?
Mycoplasma wenyonii
Severe anemia only if splenectomized (for research) or immunosuppressed cattle
Iatrogenic transmission common
May cause dependent edema (of mammary glands, scrotum, distal limbs) and lymphadenopathy without anemia
Sheep
Arrow= Mycoplasma ovis
arrow head= basophilic stippling
(normal in ruminants, lead poisenin in small animals)
Llama
Mycoplasma haemolamae
Opportunist
Causes mild anemia
Ruminant
Arrow head= normal basophilic stippling
Arrow = Anaplasma marginale or A. centrale
• Very common tick-borne rickettsial infection - world wide.
• Can cause fatal hemolytic anemia, esp in older animals
• Probably immune mediated destruction
• Diagnose blood film, PCR
• Vaccine available, rx w/ tetracycline
(Compared to Howell-jolly bodies- Anaplasma will be more numerous)
Deer. What are the arrows pointing to?
Theileriosis
Protozoan that causes hemolytic anemia in ruminants.
Theileria parva - East Coast Fever
Less pathogenic forms infect deer in U.S.
Stage of organisms within RBCs is a merozoite (piroplasm). Other stage is within macrophages which will lead to proliferation and may occlude blood vessels
Sickle cell in deer is a common in-vitro change
Arrow head = basophilic stippling due to regenerative response
Dog
Babesia gibsoni
Transmitted by ticks, blood transfusions, vertically.
Causes severe disease and hemolytic anemia.
B. gibsoni becoming important in U.S. in dogs ( since 1999) East of Mississippi
May be mistaken for IMHA
Most common in pitbull (breed? or fighting?)
Dog
Babesia canis - larger, usually 3-8 per a cell
Transmitted by ticks, blood transfusions, vertically.
Causes severe disease and hemolytic anemia.
May be mistaken for IMHA
Cat
Feline cytauxzoonosis
Protozoan
RBC phase (piroplasms) and tissue phase (schizonts in macrophages).
First described in U.S. in 1976
Transmitted by ticks, most common in Missouri.
Almost always fatal due to tissue phase
Rx with diproprionate or diminazine aceturate.
Which neutrophil precursors are proliferative?
Myeloblast
Progranulocyte
Myelocyte
If I see these cells in my peripheral blood, I have a _______ leukemia
granulocytic
These cells (at the feathered edge) are characteristic of ________ leukemia
Megakaryoblastic
What 3 things will you see in “toxic” change neutrophils? Why does this occur?
- Increase basophilia of cytoplasm
- Dohle bodies
- cytoplasmic vaculation
Occurs due to accelerated rate of production seen with inflammation, which results in persistence of ribosomes
What is up with this neutrophil? When does this occur?
Neutrophil hypersegmentation
Result of normal aging that can occur due to:
(1) In vivo- when neutrophils circulate longer, usually as a result of corticosteroids
(2) in vitro- due to againg prior to making blood film
this appearance is “kinda normal” in horses
What two things do you see in neutrophil degeneration?
Cytoplasmic vacuolation
Neutrophil swelling
…leads to cell lysis
It is seen in neutrophils not in circulation (from cytologic samples, such as an abscess, airway cytology, body cavity effusion)
Can be due to septicemia, presence of bacteria in effusions, or just in old samples
What abnormality should you suspect if you have a healthy cat with marked granulocytes in its neutrophils, but completely normal lymphocyes
Birman Cat Neutrophil Granulation Anomaly
What abnormalities do you see in Chediak-Higashi Syndrome?
Pink structes within 1/3 of neutrophils (due to lysosome fusion –> decrease function)
Abnormal platelet abnormalities –> bleeding tendencies
Melanin granule fusion –> weird silver/grey hair coat
Rare, but most commmon in persian cats
What clinical and blood signs are seen in Mucopolysaccharidosis VI lysosomal Storage Disease?
Granulation in BOTH neutrophils and lymphocytes
Skeletal Abnormaltites –> arthritis, chewing & walking problems
Cloudy eyes
What is wrong with this lymphocyte? what other clinical signs will you commonly see with this?
Lysosomal storage disease
Common to see with severe progressive neurological disease
(except and MPS and acid lipasedeficiency)
Is there adequate or inadequate cellularity?
inadequate
increased fat
____________ maturation sequence
Erythroid
___________ precursors/maturation sequence
Myeloid
What kind of cells are the arrows pointing to?
Plasma cell
What kind of cells are the arrow heads pointing to?
Mast cells
What microorganism is within these cells?
Histoplasma capsulatum
What microorganism are present (Arrow heads)?
Toxoplasma gondii
Name the microorganism
Leishmania donovani
“two dot” = nucleus & kinetoplast
What is the average lifespan of a platelet?
~5-10 days (shorter in cats)
Macroplatelets and/or an increase MPV suggest…?
increased platelet production
________ binds to GP1b on platelets (PLT) and creates a bridge between the PLT and collagen
vWF
__ _____occurs via actinomyosin filaments and filitates wound closure and vessel patency
Clot retraction
What tube should you use to measure PLT concentration?
Purple top/ EDTA
which two species have platelets that clump easily?
Cats and Cattle
At what platelet concentration will you be concerned about spontaneous hemorrhage?
Caogulation cascade?
Intrinsic= 12, 11, 9, 8
Extrinsic= 7
common= 10, 5, 2, 1
End result= Fibrin
What are the 3 important enzyme co factors for the coagulation cascade?
3 (Tissue Factor), 5a, 8a
Which of the following is false about the platelets function in secondary hemostasis?
- The Ca , secreted in the platelets granules, bind to the platelet membrane to form a positivelty charged platelet
- the platelet secretes a Va binding site
- the positive charge of the platelet draws the negatively charged coagulatiom factors (1927)
- the platelet recruits fibrinogen. which is later turned into fibrin by thrombin.
- none of the above
None of the above
What is the key factor that promotes amplification of secondary hemostasis?
***IMPORTANT****
Thrombin
True or False: Inflammatory mediators (HMWK, PK) can initiate the intrinsic pathway of the coagulation cascade?
True!
What inhibits Thrombin, IXa, Xa?
Anrithrombin (AT)
What binds to antithrombin (AT) and caises a conformational change that exposes the thrombin binding site?
Heparin!!!!
____
When thrombin binds to AT it forms the TAT complex and heprin will detach. This TAT complex is cleared by the phagocytic system
What breaks down fibrinogen and soluable fibrin into FDP, and cross-linked fibrin into D-dimers?
Plasmin
What 3 components contribute to coagulation efficiency?
Ca, platelet membrane and factor V (cofactor)
What are the two major end-products of fibrinolysis?
- Fibrin Degradation Products (FDPs)
- D-dimers
How does Vitamin K antagonism/warfarin work?
Vitamin K dependent factors lose their negative charge and are not recruited to sites of injury due to warfarin preventing the recycling of/reduction of the vitamin-K-dependent carboxylase.
