Evaluation of RBC Morphology

Question 1

Erythron

Answer 1

all RBC results, including analysis of regenerative response and morphologic features

Question 2

Leukon

Answer 2

all WBC results, including total and differential leukocyte count, and assessment of WBC morphologic features

Question 3

Thrombon

Answer 3

platelet number and size (check with slides)

Question 4

Answer 4

Avian erythrocyte - normal shape is oval

Question 5

What species’ RBCs are these?

Answer 5

Normal canine erythrocyte - note central pallor, looks like donuts

Question 6

Species?

Answer 6

normal canine erythrocytes - can tell by central pallor

Question 7

Species?

Answer 7

normal equine erythrocytes

Question 8

Species?

Answer 8

normal llama erythrocytes

Question 9

Which species?

Answer 9

normal feline erythrocytes

Question 10

species?

Answer 10

bovine

Question 11

This film demonstrates what type of RBC morphology disorder?

Answer 11

anisocytosis

Question 12

This film demonstrates what type of RBC Morphology?

Answer 12

Hypochromasia

Question 13

This film demonstrates what type of RBC Morphology?

Answer 13

Polychromasia

Question 14

Are these “bullseye” RBCs an artifact or pathological?

Answer 14

Artifact - torocytes

Question 15

This film demonstrates what type of RBC Morphology?

What species is this normal for?

Answer 15

Pokilocytosis - Normal in goats and young healthy cattle

Question 16

Match RBC shape to species. ( may have to click photo to see all)

Answer 16

Drepanocyte/sickle cell- deer

echinocyte- pig

dacrocyte - goat

ovalocyte - bird

elliptocyte - llama

Question 17

These RBCs indicate what type of changes?

Answer 17

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

Question 18

This RBC morphology change indicates what?

Answer 18

acanthocytes - liver disease, hemangiosarcoma, glomerulonephritis, DIC in dogs, normal in young goats/cattle, fragmentation when you have iron deficiency

Question 19

This RBC morphology change indicates what?

Answer 19

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

Question 20

What are these and what do they indicate?

Answer 20

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

Question 21

Name the three categories of causes of RBC fragmentation.

Answer 21

Mechanical - ie. DIC, caval syndrome from heartworms, glomerulonephritis, cardiac valvular stenosis

Endothelial - hemangiosarcoma, vasculitis, splenic/hepatic disease

Thermal - heat stroke, severe burns

Question 22

Characterize the anemia type and RBC morphologies seen with RBC fragmentation.

Answer 22

anemia is often mild/moderate and subclinical

morphologies - acanthocytes, keratocytes, schistocytes

Question 23

How can you determine if a keratocyte was created by fragmentation or oxidative injury?

Answer 23

look at its company - if there are also heinz bodies assume oxidative, if also acanthocytes and schistocytes assume fragmentation

Question 24

What bloodwork value often accompanies fragmentation and why?

Answer 24

thrombocytopenia, due to DIC

Question 25

What are these and why do they exist?

Answer 25

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

Question 26

What do spherocytes indicate?

Answer 26

**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

Question 27

What is this and would you worry about it if you only saw 3 of them?

Answer 27

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

Question 28

If you saw these RBCs in a dog or cat blood smear would you be concerned?

Answer 28

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

Question 29

What conditions would cause RBCs to look like this?

Answer 29

being a deer or angora goat hemoglobin polymerization when you have increased oxygen tension and pH

Question 30

What is your plan if you see these in a dog blood smear? Would that plan change if it was a ruminant blood smear?

Answer 30

Further diagnostics for dog - could be myelofibrosis, myeloproliferative disease, glomerulonephritis, or hypersplenism For ruminant - usually indicates iron deficiency anemia so yes plan would change

Question 31

These rectangular things are normal in the blood of what species?

Answer 31

cats and llamas rare in dogs horses - when they have metabolic protection against oxidants

Question 32

List reasons why you would see lysed erythrocytes on a blood smear.

Answer 32

IMHA Oxidant - induced hemolysis enzymatic and/or osmotic hemolysis smudged cells that look like lysed RBCs

Question 33

Which shape abnormalities are usually seen with hemangiosarcoma?

Answer 33

acanthocytes schistocytes

Question 34

Which shape abnormalities are normally seen with iron deficiency anemia?

Answer 34

hypochromasia microcytic fragmentation - keratocytes, acanthocytes, schistocytes ruminants - drepanocytes

Question 35

Which conditions have multiple shape abnormalities?

Answer 35

1. hemangiosarcoma in dogs 2. glomerulonephritis 3. myeloproliferative disorders 4. myelofibrosis 5. liver disorders 6. DIC 7. Chronic iron deficiency anemia 8. doxorubicin toxicity 9. congenital dyserythropoiesis

Question 36

What are these? Why are they important?

Answer 36

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

Question 37

What are some examples of marrow injuries that can cause nucleated erythrocytes but not necessarily anemia?

Answer 37

Septicemia endotoxic shock systemic inflammation drugs