Evaluation of RBC Morphology Flashcards
Erythron
all RBC results, including analysis of regenerative response and morphologic features
Leukon
all WBC results, including total and differential leukocyte count, and assessment of WBC morphologic features
Thrombon
platelet number and size (check with slides)
Avian erythrocyte - normal shape is oval
What species’ RBCs are these?
Normal canine erythrocyte - note central pallor, looks like donuts
Species?
normal canine erythrocytes - can tell by central pallor
Species?
normal equine erythrocytes
Species?
normal llama erythrocytes
Which species?
normal feline erythrocytes
species?
bovine
This film demonstrates what type of RBC morphology disorder?
anisocytosis
This film demonstrates what type of RBC Morphology?
Hypochromasia
This film demonstrates what type of RBC Morphology?
Polychromasia
Are these “bullseye” RBCs an artifact or pathological?
Artifact - torocytes
This film demonstrates what type of RBC Morphology?
What species is this normal for?
Pokilocytosis - Normal in goats and young healthy cattle
Match RBC shape to species. ( may have to click photo to see all)
Drepanocyte/sickle cell- deer
echinocyte- pig
dacrocyte - goat
ovalocyte - bird
elliptocyte - llama
These RBCs indicate what type of changes?
These are echinocytes - indicate crenation, a reversible shape change.
Usually an artifact but can be due to snake bites, uremia, post transfusion PK deficiency, glomerulonephritis, neoplasia, doxorubicin, RBC dehydration, ATP depletion, increased pH, increased RBC calcium
This RBC morphology change indicates what?
acanthocytes - liver disease, hemangiosarcoma, glomerulonephritis, DIC in dogs, normal in young goats/cattle, fragmentation when you have iron deficiency
This RBC morphology change indicates what?
keratocytes - iron deficiency anemia due to fragmentation, liver disorders, various disorders associated with acanthocytosis such as DIC, doxorubicin toxicity in cats, formation potentiated by blood storage in cats
What are these and what do they indicate?
Schistocytes - fragmented cells usually due to DIC in dogs, severe iron deficiency, liver disease, hemangiosarcoma in dogs, myelofibrosis, glomerulonephritis, histiocytic disorders, PK deficiency post splenectomy
Name the three categories of causes of RBC fragmentation.
Mechanical - ie. DIC, caval syndrome from heartworms, glomerulonephritis, cardiac valvular stenosis
Endothelial - hemangiosarcoma, vasculitis, splenic/hepatic disease
Thermal - heat stroke, severe burns
Characterize the anemia type and RBC morphologies seen with RBC fragmentation.
anemia is often mild/moderate and subclinical
morphologies - acanthocytes, keratocytes, schistocytes
How can you determine if a keratocyte was created by fragmentation or oxidative injury?
look at its company - if there are also heinz bodies assume oxidative, if also acanthocytes and schistocytes assume fragmentation
What bloodwork value often accompanies fragmentation and why?
thrombocytopenia, due to DIC
What are these and why do they exist?
stomatocytes - often artifact in thick blood films, hereditary (will see swollen RBCs with increased MCV and decreased MCHC), drugs that preferentially bind to inner half of lipid bilayer
What do spherocytes indicate?
IMHA (esp. in dogs)
snake bites, bee stings
zinc toxicity
hemoparasites
transfusion of stored blood
dyserythropoiesis in English springers, RBC band 3 deficiency in Japanese black cattle, partial spectrin disorder in golden retrivers
What is this and would you worry about it if you only saw 3 of them?
Leptocytes (ie. codocytes and knizocytes)
no - low numbers in normal dogs
increased in canine regenerative anemia, iron deficiency anemia, rarely liver disease, congenital dyserythropoiesis in English springers
If you saw these RBCs in a dog or cat blood smear would you be concerned?
Yes - they are elliptocytes, only normal for camelidae
in cats - marrow abnormalities, hepatic lipidosis, portosystemic shunts, doxorubicin toxicity
dogs - myelofibrosis, myelodysplastic syndrome, glomerulonephritis, hereditary RBC band deficiency
What conditions would cause RBCs to look like this?
being a deer or angora goat
hemoglobin polymerization when you have increased oxygen tension and pH
What is your plan if you see these in a dog blood smear?
Would that plan change if it was a ruminant blood smear?
Further diagnostics for dog - could be myelofibrosis, myeloproliferative disease, glomerulonephritis, or hypersplenism
For ruminant - usually indicates iron deficiency anemia so yes plan would change
These rectangular things are normal in the blood of what species?
cats and llamas
rare in dogs
horses - when they have metabolic protection against oxidants
List reasons why you would see lysed erythrocytes on a blood smear.
IMHA
Oxidant - induced hemolysis
enzymatic and/or osmotic hemolysis
smudged cells that look like lysed RBCs
Which shape abnormalities are usually seen with hemangiosarcoma?
acanthocytes
schistocytes
Which shape abnormalities are normally seen with iron deficiency anemia?
hypochromasia
microcytic
fragmentation - keratocytes, acanthocytes, schistocytes
ruminants - drepanocytes
Which conditions have multiple shape abnormalities?
- hemangiosarcoma in dogs
- glomerulonephritis
- myeloproliferative disorders
- myelofibrosis
- liver disorders
- DIC
- Chronic iron deficiency anemia
- doxorubicin toxicity
- congenital dyserythropoiesis
What are these? Why are they important?
nucleated erythrocytes - usually metarubricytes and rubricytes
present in low numbers in healthy cats/dogs
indicative of: regnerative anemias, lead toxicity, marrow injury/disease, various disorders (cardio, inflammatory, trauma, hyperadrenocorticism in dogs, hepatic lipidosis in cats), splenic dysfunction, hereditary dyserythropoiesis
What are some examples of marrow injuries that can cause nucleated erythrocytes but not necessarily anemia?
Septicemia
endotoxic shock
systemic inflammation
drugs
